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* [PATCH v12 2/7] Row pattern recognition patch (parse/analysis).
@ 2023-12-04 11:23 Tatsuo Ishii <[email protected]>
0 siblings, 0 replies; 5+ messages in thread
From: Tatsuo Ishii @ 2023-12-04 11:23 UTC (permalink / raw)
---
src/backend/parser/parse_agg.c | 7 +
src/backend/parser/parse_clause.c | 278 +++++++++++++++++++++++++++++-
src/backend/parser/parse_expr.c | 4 +
src/backend/parser/parse_func.c | 3 +
4 files changed, 291 insertions(+), 1 deletion(-)
diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c
index 9bbad33fbd..28fb5e0d71 100644
--- a/src/backend/parser/parse_agg.c
+++ b/src/backend/parser/parse_agg.c
@@ -575,6 +575,10 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr)
errkind = true;
break;
+ case EXPR_KIND_RPR_DEFINE:
+ errkind = true;
+ break;
+
/*
* There is intentionally no default: case here, so that the
* compiler will warn if we add a new ParseExprKind without
@@ -964,6 +968,9 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc,
case EXPR_KIND_CYCLE_MARK:
errkind = true;
break;
+ case EXPR_KIND_RPR_DEFINE:
+ errkind = true;
+ break;
/*
* There is intentionally no default: case here, so that the
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index 334b9b42bd..c5d3c10683 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -100,7 +100,10 @@ static WindowClause *findWindowClause(List *wclist, const char *name);
static Node *transformFrameOffset(ParseState *pstate, int frameOptions,
Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc,
Node *clause);
-
+static void transformRPR(ParseState *pstate, WindowClause *wc, WindowDef *windef, List **targetlist);
+static List *transformDefineClause(ParseState *pstate, WindowClause *wc, WindowDef *windef, List **targetlist);
+static void transformPatternClause(ParseState *pstate, WindowClause *wc, WindowDef *windef);
+static List *transformMeasureClause(ParseState *pstate, WindowClause *wc, WindowDef *windef);
/*
* transformFromClause -
@@ -2950,6 +2953,10 @@ transformWindowDefinitions(ParseState *pstate,
rangeopfamily, rangeopcintype,
&wc->endInRangeFunc,
windef->endOffset);
+
+ /* Process Row Pattern Recognition related clauses */
+ transformRPR(pstate, wc, windef, targetlist);
+
wc->runCondition = NIL;
wc->winref = winref;
@@ -3815,3 +3822,272 @@ transformFrameOffset(ParseState *pstate, int frameOptions,
return node;
}
+
+/*
+ * transformRPR
+ * Process Row Pattern Recognition related clauses
+ */
+static void
+transformRPR(ParseState *pstate, WindowClause *wc, WindowDef *windef, List **targetlist)
+{
+ /*
+ * Window definition exists?
+ */
+ if (windef == NULL)
+ return;
+
+ /*
+ * Row Pattern Common Syntax clause exists?
+ */
+ if (windef->rpCommonSyntax == NULL)
+ return;
+
+ /* Check Frame option. Frame must start at current row */
+ if ((wc->frameOptions & FRAMEOPTION_START_CURRENT_ROW) == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("FRAME must start at current row when row patttern recognition is used")));
+
+ /* Transform AFTER MACH SKIP TO clause */
+ wc->rpSkipTo = windef->rpCommonSyntax->rpSkipTo;
+
+ /* Transform SEEK or INITIAL clause */
+ wc->initial = windef->rpCommonSyntax->initial;
+
+ /* Transform DEFINE clause into list of TargetEntry's */
+ wc->defineClause = transformDefineClause(pstate, wc, windef, targetlist);
+
+ /* Check PATTERN clause and copy to patternClause */
+ transformPatternClause(pstate, wc, windef);
+
+ /* Transform MEASURE clause */
+ transformMeasureClause(pstate, wc, windef);
+}
+
+/*
+ * transformDefineClause Process DEFINE clause and transform ResTarget into
+ * list of TargetEntry.
+ *
+ * XXX we only support column reference in row pattern definition search
+ * condition, e.g. "price". <row pattern definition variable name>.<column
+ * reference> is not supported, e.g. "A.price".
+ */
+static List *
+transformDefineClause(ParseState *pstate, WindowClause *wc, WindowDef *windef, List **targetlist)
+{
+ /* DEFINE variable name initials */
+ static char *defineVariableInitials = "abcdefghijklmnopqrstuvwxyz";
+
+ ListCell *lc, *l;
+ ResTarget *restarget, *r;
+ List *restargets;
+ List *defineClause;
+ char *name;
+ int initialLen;
+ int i;
+
+ /*
+ * If Row Definition Common Syntax exists, DEFINE clause must exist.
+ * (the raw parser should have already checked it.)
+ */
+ Assert(windef->rpCommonSyntax->rpDefs != NULL);
+
+ /*
+ * Check and add "A AS A IS TRUE" if pattern variable is missing in DEFINE
+ * per the SQL standard.
+ */
+ restargets = NIL;
+ foreach(lc, windef->rpCommonSyntax->rpPatterns)
+ {
+ A_Expr *a;
+ bool found = false;
+
+ if (!IsA(lfirst(lc), A_Expr))
+ ereport(ERROR,
+ errmsg("node type is not A_Expr"));
+
+ a = (A_Expr *)lfirst(lc);
+ name = strVal(a->lexpr);
+
+ foreach(l, windef->rpCommonSyntax->rpDefs)
+ {
+ restarget = (ResTarget *)lfirst(l);
+
+ if (!strcmp(restarget->name, name))
+ {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ {
+ /*
+ * "name" is missing. So create "name AS name IS TRUE" ResTarget
+ * node and add it to the temporary list.
+ */
+ A_Const *n;
+
+ restarget = makeNode(ResTarget);
+ n = makeNode(A_Const);
+ n->val.boolval.type = T_Boolean;
+ n->val.boolval.boolval = true;
+ n->location = -1;
+ restarget->name = pstrdup(name);
+ restarget->indirection = NIL;
+ restarget->val = (Node *)n;
+ restarget->location = -1;
+ restargets = lappend((List *)restargets, restarget);
+ }
+ }
+
+ if (list_length(restargets) >= 1)
+ {
+ /* add missing DEFINEs */
+ windef->rpCommonSyntax->rpDefs = list_concat(windef->rpCommonSyntax->rpDefs,
+ restargets);
+ list_free(restargets);
+ }
+
+ /*
+ * Check for duplicate row pattern definition variables. The standard
+ * requires that no two row pattern definition variable names shall be
+ * equivalent.
+ */
+ restargets = NIL;
+ foreach(lc, windef->rpCommonSyntax->rpDefs)
+ {
+ restarget = (ResTarget *)lfirst(lc);
+ name = restarget->name;
+
+ /*
+ * Add DEFINE expression (Restarget->val) to the targetlist as a
+ * TargetEntry if it does not exist yet. Planner will add the column
+ * ref var node to the outer plan's target list later on. This makes
+ * DEFINE expression could access the outer tuple while evaluating
+ * PATTERN.
+ *
+ * XXX: adding whole expressions of DEFINE to the plan.targetlist is
+ * not so good, because it's not necessary to evalute the expression
+ * in the target list while running the plan. We should extract the
+ * var nodes only then add them to the plan.targetlist.
+ */
+ findTargetlistEntrySQL99(pstate, (Node *)restarget->val, targetlist, EXPR_KIND_RPR_DEFINE);
+
+ /*
+ * Make sure that the row pattern definition search condition is a
+ * boolean expression.
+ */
+ transformWhereClause(pstate, restarget->val,
+ EXPR_KIND_RPR_DEFINE, "DEFINE");
+
+ foreach(l, restargets)
+ {
+ char *n;
+
+ r = (ResTarget *) lfirst(l);
+ n = r->name;
+
+ if (!strcmp(n, name))
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("row pattern definition variable name \"%s\" appears more than once in DEFINE clause",
+ name),
+ parser_errposition(pstate, exprLocation((Node *)r))));
+ }
+ restargets = lappend(restargets, restarget);
+ }
+ list_free(restargets);
+
+ /*
+ * Create list of row pattern DEFINE variable name's initial.
+ * We assign [a-z] to them (up to 26 variable names are allowed).
+ */
+ restargets = NIL;
+ i = 0;
+ initialLen = strlen(defineVariableInitials);
+
+ foreach(lc, windef->rpCommonSyntax->rpDefs)
+ {
+ char initial[2];
+
+ restarget = (ResTarget *)lfirst(lc);
+ name = restarget->name;
+
+ if (i >= initialLen)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("number of row pattern definition variable names exceeds %d", initialLen),
+ parser_errposition(pstate, exprLocation((Node *)restarget))));
+ }
+ initial[0] = defineVariableInitials[i++];
+ initial[1] = '\0';
+ wc->defineInitial = lappend(wc->defineInitial, makeString(pstrdup(initial)));
+ }
+
+ defineClause = transformTargetList(pstate, windef->rpCommonSyntax->rpDefs,
+ EXPR_KIND_RPR_DEFINE);
+
+ /* mark column origins */
+ markTargetListOrigins(pstate, defineClause);
+
+ /* mark all nodes in the DEFINE clause tree with collation information */
+ assign_expr_collations(pstate, (Node *)defineClause);
+
+ return defineClause;
+}
+
+/*
+ * transformPatternClause
+ * Process PATTERN clause and return PATTERN clause in the raw parse tree
+ */
+static void
+transformPatternClause(ParseState *pstate, WindowClause *wc, WindowDef *windef)
+{
+ ListCell *lc;
+
+ /*
+ * Row Pattern Common Syntax clause exists?
+ */
+ if (windef->rpCommonSyntax == NULL)
+ return;
+
+ wc->patternVariable = NIL;
+ wc->patternRegexp = NIL;
+ foreach(lc, windef->rpCommonSyntax->rpPatterns)
+ {
+ A_Expr *a;
+ char *name;
+ char *regexp;
+
+ if (!IsA(lfirst(lc), A_Expr))
+ ereport(ERROR,
+ errmsg("node type is not A_Expr"));
+
+ a = (A_Expr *)lfirst(lc);
+ name = strVal(a->lexpr);
+
+ wc->patternVariable = lappend(wc->patternVariable, makeString(pstrdup(name)));
+ regexp = strVal(lfirst(list_head(a->name)));
+ wc->patternRegexp = lappend(wc->patternRegexp, makeString(pstrdup(regexp)));
+ }
+}
+
+/*
+ * transformMeasureClause
+ * Process MEASURE clause
+ * XXX MEASURE clause is not supported yet
+ */
+static List *
+transformMeasureClause(ParseState *pstate, WindowClause *wc, WindowDef *windef)
+{
+ if (windef->rowPatternMeasures == NIL)
+ return NIL;
+
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("%s","MEASURE clause is not supported yet"),
+ parser_errposition(pstate, exprLocation((Node *)windef->rowPatternMeasures))));
+ return NIL;
+}
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 64c582c344..18b58ac263 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -557,6 +557,7 @@ transformColumnRef(ParseState *pstate, ColumnRef *cref)
case EXPR_KIND_COPY_WHERE:
case EXPR_KIND_GENERATED_COLUMN:
case EXPR_KIND_CYCLE_MARK:
+ case EXPR_KIND_RPR_DEFINE:
/* okay */
break;
@@ -1770,6 +1771,7 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
case EXPR_KIND_VALUES:
case EXPR_KIND_VALUES_SINGLE:
case EXPR_KIND_CYCLE_MARK:
+ case EXPR_KIND_RPR_DEFINE:
/* okay */
break;
case EXPR_KIND_CHECK_CONSTRAINT:
@@ -3149,6 +3151,8 @@ ParseExprKindName(ParseExprKind exprKind)
return "GENERATED AS";
case EXPR_KIND_CYCLE_MARK:
return "CYCLE";
+ case EXPR_KIND_RPR_DEFINE:
+ return "DEFINE";
/*
* There is intentionally no default: case here, so that the
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 6c29471bb3..086431f91b 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -2656,6 +2656,9 @@ check_srf_call_placement(ParseState *pstate, Node *last_srf, int location)
case EXPR_KIND_CYCLE_MARK:
errkind = true;
break;
+ case EXPR_KIND_RPR_DEFINE:
+ errkind = true;
+ break;
/*
* There is intentionally no default: case here, so that the
--
2.25.1
----Next_Part(Fri_Dec__8_10_16_13_2023_489)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v12-0003-Row-pattern-recognition-patch-planner.patch"
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Potential ABI breakage in upcoming minor releases
@ 2024-11-14 20:06 Alvaro Herrera <[email protected]>
2024-11-14 20:09 ` Re: Potential ABI breakage in upcoming minor releases Tom Lane <[email protected]>
0 siblings, 1 reply; 5+ messages in thread
From: Alvaro Herrera @ 2024-11-14 20:06 UTC (permalink / raw)
To: Christoph Berg <[email protected]>; Noah Misch <[email protected]>; Pavan Deolasee <[email protected]>; pgsql-hackers; Tom Lane <[email protected]>
On 2024-Nov-14, Christoph Berg wrote:
> It didn't actually crash, true.
But timescale did crash:
https://pgdgbuild.dus.dg-i.net/job/timescaledb-autopkgtest/9/architecture=amd64,distribution=sid/con...
11:59:51 @@ -34,6 +40,7 @@
11:59:51 CREATE INDEX ON _hyper_1_3_chunk(temp2);
11:59:51 -- INSERT only will not trigger vacuum on indexes for PG13.3+
11:59:51 UPDATE vacuum_test SET time = time + '1s'::interval, temp1 = random(), temp2 = random();
11:59:51 --- we should see two parallel workers for each chunk
11:59:51 -VACUUM (PARALLEL 3) vacuum_test;
11:59:51 -DROP TABLE vacuum_test;
11:59:51 +server closed the connection unexpectedly
11:59:51 + This probably means the server terminated abnormally
11:59:51 + before or while processing the request.
11:59:51 +connection to server was lost
--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
"El Maquinismo fue proscrito so pena de cosquilleo hasta la muerte"
(Ijon Tichy en Viajes, Stanislaw Lem)
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Potential ABI breakage in upcoming minor releases
2024-11-14 20:06 Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
@ 2024-11-14 20:09 ` Tom Lane <[email protected]>
2024-11-14 20:33 ` Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
0 siblings, 1 reply; 5+ messages in thread
From: Tom Lane @ 2024-11-14 20:09 UTC (permalink / raw)
To: Alvaro Herrera <[email protected]>; +Cc: Christoph Berg <[email protected]>; Noah Misch <[email protected]>; Pavan Deolasee <[email protected]>; pgsql-hackers
Alvaro Herrera <[email protected]> writes:
> On 2024-Nov-14, Christoph Berg wrote:
>> It didn't actually crash, true.
> But timescale did crash:
So what is timescale doing differently?
regards, tom lane
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Potential ABI breakage in upcoming minor releases
2024-11-14 20:06 Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
2024-11-14 20:09 ` Re: Potential ABI breakage in upcoming minor releases Tom Lane <[email protected]>
@ 2024-11-14 20:33 ` Alvaro Herrera <[email protected]>
2024-11-14 20:44 ` Re: Potential ABI breakage in upcoming minor releases Aleksander Alekseev <[email protected]>
0 siblings, 1 reply; 5+ messages in thread
From: Alvaro Herrera @ 2024-11-14 20:33 UTC (permalink / raw)
To: Tom Lane <[email protected]>; +Cc: Christoph Berg <[email protected]>; Noah Misch <[email protected]>; Pavan Deolasee <[email protected]>; pgsql-hackers
On 2024-Nov-14, Tom Lane wrote:
> Alvaro Herrera <[email protected]> writes:
> > On 2024-Nov-14, Christoph Berg wrote:
> >> It didn't actually crash, true.
>
> > But timescale did crash:
>
> So what is timescale doing differently?
No idea. Maybe a stacktrace from a core would tell us more; but the
jenkins task doesn't seem to have server logs or anything else to gives
us more clues.
There are three makeNode(ResultRelInfo), but they don't look anything
out of the ordinary:
C perhan: timescaledb 0$ git grep -C5 makeNode.ResultRelInfo
src/copy.c- *
src/copy.c- * WARNING. The dummy rangetable index is decremented by 1 (unchecked)
src/copy.c- * inside `ExecConstraints` so unless you want to have a overflow, keep it
src/copy.c- * above zero. See `rt_fetch` in parsetree.h.
src/copy.c- */
src/copy.c: resultRelInfo = makeNode(ResultRelInfo);
src/copy.c-
src/copy.c-#if PG16_LT
src/copy.c- ExecInitRangeTable(estate, pstate->p_rtable);
src/copy.c-#else
src/copy.c- Assert(pstate->p_rteperminfos != NULL);
--
src/nodes/chunk_dispatch/chunk_insert_state.c-create_chunk_result_relation_info(const ChunkDispatch *dispatch, Relation rel)
src/nodes/chunk_dispatch/chunk_insert_state.c-{
src/nodes/chunk_dispatch/chunk_insert_state.c- ResultRelInfo *rri;
src/nodes/chunk_dispatch/chunk_insert_state.c- ResultRelInfo *rri_orig = dispatch->hypertable_result_rel_info;
src/nodes/chunk_dispatch/chunk_insert_state.c- Index hyper_rti = rri_orig->ri_RangeTableIndex;
src/nodes/chunk_dispatch/chunk_insert_state.c: rri = makeNode(ResultRelInfo);
src/nodes/chunk_dispatch/chunk_insert_state.c-
src/nodes/chunk_dispatch/chunk_insert_state.c- InitResultRelInfo(rri, rel, hyper_rti, NULL, dispatch->estate->es_instrument);
src/nodes/chunk_dispatch/chunk_insert_state.c-
src/nodes/chunk_dispatch/chunk_insert_state.c- /* Copy options from the main table's (hypertable's) result relation info */
src/nodes/chunk_dispatch/chunk_insert_state.c- rri->ri_WithCheckOptions = rri_orig->ri_WithCheckOptions;
--
src/ts_catalog/catalog.c-extern TSDLLEXPORT ResultRelInfo *
src/ts_catalog/catalog.c-ts_catalog_open_indexes(Relation heapRel)
src/ts_catalog/catalog.c-{
src/ts_catalog/catalog.c- ResultRelInfo *resultRelInfo;
src/ts_catalog/catalog.c-
src/ts_catalog/catalog.c: resultRelInfo = makeNode(ResultRelInfo);
src/ts_catalog/catalog.c- resultRelInfo->ri_RangeTableIndex = 0; /* dummy */
src/ts_catalog/catalog.c- resultRelInfo->ri_RelationDesc = heapRel;
src/ts_catalog/catalog.c- resultRelInfo->ri_TrigDesc = NULL; /* we don't fire triggers */
src/ts_catalog/catalog.c-
src/ts_catalog/catalog.c- ExecOpenIndices(resultRelInfo, false);
I didn't catch any other allocations that would depend on the size of
ResultRelInfo in obvious ways.
Oh, hmm, there's this bit which uses struct assignment into a stack
element:
tsl/src/compression/compression.c-1559- if (decompressor->indexstate->ri_NumIndices > 0)
tsl/src/compression/compression.c-1560- {
tsl/src/compression/compression.c:1561: ResultRelInfo indexstate_copy = *decompressor->indexstate;
tsl/src/compression/compression.c-1562- Relation single_index_relation;
I find this rather suspect.
--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
"La espina, desde que nace, ya pincha" (Proverbio africano)
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Potential ABI breakage in upcoming minor releases
2024-11-14 20:06 Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
2024-11-14 20:09 ` Re: Potential ABI breakage in upcoming minor releases Tom Lane <[email protected]>
2024-11-14 20:33 ` Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
@ 2024-11-14 20:44 ` Aleksander Alekseev <[email protected]>
0 siblings, 0 replies; 5+ messages in thread
From: Aleksander Alekseev @ 2024-11-14 20:44 UTC (permalink / raw)
To: pgsql-hackers; +Cc: Tom Lane <[email protected]>; Alvaro Herrera <[email protected]>; Christoph Berg <[email protected]>; Noah Misch <[email protected]>; Pavan Deolasee <[email protected]>
Hi Alvaro,
> There are three makeNode(ResultRelInfo), but they don't look anything
> out of the ordinary:
> [...]
> src/ts_catalog/catalog.c-extern TSDLLEXPORT ResultRelInfo *
> src/ts_catalog/catalog.c-ts_catalog_open_indexes(Relation heapRel)
> src/ts_catalog/catalog.c-{
> src/ts_catalog/catalog.c- ResultRelInfo *resultRelInfo;
> src/ts_catalog/catalog.c-
> src/ts_catalog/catalog.c: resultRelInfo = makeNode(ResultRelInfo);
> src/ts_catalog/catalog.c- resultRelInfo->ri_RangeTableIndex = 0; /* dummy */
> src/ts_catalog/catalog.c- resultRelInfo->ri_RelationDesc = heapRel;
> src/ts_catalog/catalog.c- resultRelInfo->ri_TrigDesc = NULL; /* we don't fire triggers */
> src/ts_catalog/catalog.c-
> src/ts_catalog/catalog.c- ExecOpenIndices(resultRelInfo, false);
ExecOpenIndices() will not fill the ri_needLockTagTuple field for the
caller and it will contain garbage.
Since you assumed this is the correct usage, maybe it should?
--
Best regards,
Aleksander Alekseev
^ permalink raw reply [nested|flat] 5+ messages in thread
end of thread, other threads:[~2024-11-14 20:44 UTC | newest]
Thread overview: 5+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2023-12-04 11:23 [PATCH v12 2/7] Row pattern recognition patch (parse/analysis). Tatsuo Ishii <[email protected]>
2024-11-14 20:06 Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
2024-11-14 20:09 ` Re: Potential ABI breakage in upcoming minor releases Tom Lane <[email protected]>
2024-11-14 20:33 ` Re: Potential ABI breakage in upcoming minor releases Alvaro Herrera <[email protected]>
2024-11-14 20:44 ` Re: Potential ABI breakage in upcoming minor releases Aleksander Alekseev <[email protected]>
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