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help / color / mirror / Atom feed[PATCH v21 2/8] Row pattern recognition patch (parse/analysis).
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* [PATCH v21 2/8] Row pattern recognition patch (parse/analysis).
@ 2024-08-26 04:32 Tatsuo Ishii <[email protected]>
0 siblings, 0 replies; 3+ messages in thread
From: Tatsuo Ishii @ 2024-08-26 04:32 UTC (permalink / raw)
---
src/backend/parser/parse_agg.c | 7 +
src/backend/parser/parse_clause.c | 296 +++++++++++++++++++++++++++++-
src/backend/parser/parse_expr.c | 6 +
src/backend/parser/parse_func.c | 3 +
4 files changed, 311 insertions(+), 1 deletion(-)
diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c
index bee7d8346a..9bc22a836a 100644
--- a/src/backend/parser/parse_agg.c
+++ b/src/backend/parser/parse_agg.c
@@ -577,6 +577,10 @@ 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
@@ -967,6 +971,9 @@ 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 8118036495..9762dce81f 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -98,7 +98,14 @@ 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 -
@@ -2956,6 +2963,10 @@ transformWindowDefinitions(ParseState *pstate,
rangeopfamily, rangeopcintype,
&wc->endInRangeFunc,
windef->endOffset);
+
+ /* Process Row Pattern Recognition related clauses */
+ transformRPR(pstate, wc, windef, targetlist);
+
wc->winref = winref;
result = lappend(result, wc);
@@ -3820,3 +3831,286 @@ 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 AFTER MACH SKIP TO variable */
+ wc->rpSkipVariable = windef->rpCommonSyntax->rpSkipVariable;
+
+ /* 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 56e413da9f..c187b3278d 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -577,6 +577,7 @@ 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;
@@ -1860,6 +1861,9 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
case EXPR_KIND_GENERATED_COLUMN:
err = _("cannot use subquery in column generation expression");
break;
+ case EXPR_KIND_RPR_DEFINE:
+ err = _("cannot use subquery in DEFINE expression");
+ break;
/*
* There is intentionally no default: case here, so that the
@@ -3199,6 +3203,8 @@ 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 9b23344a3b..4c482abb30 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -2658,6 +2658,9 @@ 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(Mon_Aug_26_13_39_47_2024_878)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v21-0003-Row-pattern-recognition-patch-rewriter.patch"
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: not null constraints, again
@ 2024-11-07 07:10 jian he <[email protected]>
0 siblings, 1 reply; 3+ messages in thread
From: jian he @ 2024-11-07 07:10 UTC (permalink / raw)
To: Alvaro Herrera <[email protected]>; +Cc: Pg Hackers <[email protected]>; Tender Wang <[email protected]>
RemoveInheritance
if (copy_con->coninhcount <= 0) /* shouldn't happen */
elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
RelationGetRelid(child_rel), NameStr(copy_con->conname));
dropconstraint_internal
if (childcon->coninhcount <= 0) /* shouldn't happen */
elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
childrelid, NameStr(childcon->conname));
RemoveInheritance error triggered (see below), dropconstraint_internal may also.
that means the error message should use RelationGetRelationName
rather than plain "relation %u"?
drop table if exists inh_parent,inh_child1,inh_child2;
create table inh_parent(f1 int not null no inherit);
create table inh_child1(f1 int not null no inherit);
alter table inh_child1 inherit inh_parent;
alter table inh_child1 NO INHERIT inh_parent;
ERROR: relation 26387 has non-inherited constraint "inh_child1_f1_not_null"
sql-altertable.html
INHERIT parent_table
This form adds the target table as a new child of the
specified parent table.
Subsequently, queries against the parent will include records
of the target
table. To be added as a child, the target table must already
contain all the
same columns as the parent (it could have additional columns,
too). The columns
must have matching data types, and if they have NOT NULL
constraints in the
parent then they must also have NOT NULL constraints in the child.
"
The columns must have matching data types, and if they have NOT NULL
constraints in the
parent then they must also have NOT NULL constraints in the child.
"
For the above sentence, we need to add some text to explain
NOT NULL constraints, NO INHERIT property
for the child table and parent table.
------------------------------------------------
drop table if exists inh_parent,inh_child1,inh_child2;
create table inh_parent(f1 int not null no inherit);
create table inh_child1(f1 int);
alter table inh_child1 inherit inh_parent;
alter table inh_child1 NO INHERIT inh_parent;
ERROR: 1 unmatched constraints while removing inheritance from
"inh_child1" to "inh_parent"
now, we cannot "uninherit" inh_child1 from inh_parent?
not sure this is expected behavior.
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: not null constraints, again
@ 2024-11-07 16:48 Alvaro Herrera <[email protected]>
parent: jian he <[email protected]>
0 siblings, 0 replies; 3+ messages in thread
From: Alvaro Herrera @ 2024-11-07 16:48 UTC (permalink / raw)
To: jian he <[email protected]>; +Cc: Pg Hackers <[email protected]>; Tender Wang <[email protected]>
On 2024-Nov-07, jian he wrote:
> RemoveInheritance
> if (copy_con->coninhcount <= 0) /* shouldn't happen */
> elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
> RelationGetRelid(child_rel), NameStr(copy_con->conname));
> dropconstraint_internal
> if (childcon->coninhcount <= 0) /* shouldn't happen */
> elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
> childrelid, NameStr(childcon->conname));
>
> RemoveInheritance error triggered (see below), dropconstraint_internal may also.
> that means the error message should use RelationGetRelationName
> rather than plain "relation %u"?
>
> drop table if exists inh_parent,inh_child1,inh_child2;
> create table inh_parent(f1 int not null no inherit);
> create table inh_child1(f1 int not null no inherit);
> alter table inh_child1 inherit inh_parent;
> alter table inh_child1 NO INHERIT inh_parent;
> ERROR: relation 26387 has non-inherited constraint "inh_child1_f1_not_null"
Hmm, no, this is just a code bug: in RemoveInheritance when scanning
'parent' for constraints, we must skip the ones that are NO INHERIT, but
weren't. With the bug fixed, the sequence above results in a
no-longer-child inh_child1 that still has inh_child1_f1_not_null, and no
error is thrown.
> sql-altertable.html
> INHERIT parent_table
> This form adds the target table as a new child of the specified parent table.
> Subsequently, queries against the parent will include records of the target
> table. To be added as a child, the target table must already contain all the
> same columns as the parent (it could have additional columns, too). The columns
> must have matching data types, and if they have NOT NULL constraints in the
> parent then they must also have NOT NULL constraints in the child.
>
> "
> The columns must have matching data types, and if they have NOT NULL
> constraints in the
> parent then they must also have NOT NULL constraints in the child.
> "
> For the above sentence, we need to add some text to explain
> NOT NULL constraints, NO INHERIT property
> for the child table and parent table.
True. I rewrote as follows, moving the whole explanation of constraints
together to the same paragraph, rather than talking about some
constraints in one paragraph and other constraints in another. The
previous approach was better when NOT NULL markings were a property of
the column, but now that they are constraints in their own right, this
seems better.
<term><literal>INHERIT <replaceable class="parameter">parent_table</replaceable></literal></term>
<listitem>
<para>
This form adds the target table as a new child of the specified parent
table. Subsequently, queries against the parent will include records
of the target table. To be added as a child, the target table must
already contain all the same columns as the parent (it could have
additional columns, too). The columns must have matching data types.
</para>
<para>
In addition, all <literal>CHECK</literal> and <literal>NOT NULL</literal>
constraints on the parent must also exist on the child, except those
marked non-inheritable (that is, created with
<literal>ALTER TABLE ... ADD CONSTRAINT ... NO INHERIT</literal>), which
are ignored. All child-table constraints matched must not be marked
non-inheritable. Currently
<literal>UNIQUE</literal>, <literal>PRIMARY KEY</literal>, and
<literal>FOREIGN KEY</literal> constraints are not considered, but
this might change in the future.
</para>
</listitem>
> ------------------------------------------------
> drop table if exists inh_parent,inh_child1,inh_child2;
> create table inh_parent(f1 int not null no inherit);
> create table inh_child1(f1 int);
> alter table inh_child1 inherit inh_parent;
> alter table inh_child1 NO INHERIT inh_parent;
> ERROR: 1 unmatched constraints while removing inheritance from "inh_child1" to "inh_parent"
>
> now, we cannot "uninherit" inh_child1 from inh_parent?
> not sure this is expected behavior.
Yeah, this is the same bug as above.
--
Álvaro Herrera Breisgau, Deutschland — https://www.EnterpriseDB.com/
"In fact, the basic problem with Perl 5's subroutines is that they're not
crufty enough, so the cruft leaks out into user-defined code instead, by
the Conservation of Cruft Principle." (Larry Wall, Apocalypse 6)
^ permalink raw reply [nested|flat] 3+ messages in thread
end of thread, other threads:[~2024-11-07 16:48 UTC | newest]
Thread overview: 3+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2024-08-26 04:32 [PATCH v21 2/8] Row pattern recognition patch (parse/analysis). Tatsuo Ishii <[email protected]>
2024-11-07 07:10 Re: not null constraints, again jian he <[email protected]>
2024-11-07 16:48 ` Re: not null constraints, again Alvaro Herrera <[email protected]>
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