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-rw-r--r--src/backend/optimizer/plan/subselect.c132
1 files changed, 68 insertions, 64 deletions
diff --git a/src/backend/optimizer/plan/subselect.c b/src/backend/optimizer/plan/subselect.c
index 7e5d2be749e..5290c96d5db 100644
--- a/src/backend/optimizer/plan/subselect.c
+++ b/src/backend/optimizer/plan/subselect.c
@@ -6,7 +6,7 @@
* Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/subselect.c,v 1.24 1999/08/25 23:21:39 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/subselect.c,v 1.25 1999/11/15 02:00:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -173,10 +173,43 @@ make_subplan(SubLink *slink)
}
/*
- * Un-correlated or undirect correlated plans of EXISTS or EXPR types
- * can be used as initPlans...
+ * Un-correlated or undirect correlated plans of EXISTS, EXPR, or
+ * MULTIEXPR types can be used as initPlans. For EXISTS or EXPR,
+ * we just produce a Param referring to the result of evaluating the
+ * initPlan. For MULTIEXPR, we must build an AND or OR-clause of the
+ * individual comparison operators, using the appropriate lefthand
+ * side expressions and Params for the initPlan's target items.
*/
- if (node->parParam == NULL && slink->subLinkType == EXPR_SUBLINK)
+ if (node->parParam == NIL && slink->subLinkType == EXISTS_SUBLINK)
+ {
+ Var *var = makeVar(0, 0, BOOLOID, -1, 0);
+ Param *prm = makeNode(Param);
+
+ prm->paramkind = PARAM_EXEC;
+ prm->paramid = (AttrNumber) new_param(var, PlannerQueryLevel);
+ prm->paramtype = var->vartype;
+ pfree(var); /* var is only needed for new_param */
+ node->setParam = lappendi(node->setParam, prm->paramid);
+ PlannerInitPlan = lappend(PlannerInitPlan, node);
+ result = (Node *) prm;
+ }
+ else if (node->parParam == NIL && slink->subLinkType == EXPR_SUBLINK)
+ {
+ TargetEntry *te = lfirst(plan->targetlist);
+ /* need a var node just to pass to new_param()... */
+ Var *var = makeVar(0, 0, te->resdom->restype,
+ te->resdom->restypmod, 0);
+ Param *prm = makeNode(Param);
+
+ prm->paramkind = PARAM_EXEC;
+ prm->paramid = (AttrNumber) new_param(var, PlannerQueryLevel);
+ prm->paramtype = var->vartype;
+ pfree(var); /* var is only needed for new_param */
+ node->setParam = lappendi(node->setParam, prm->paramid);
+ PlannerInitPlan = lappend(PlannerInitPlan, node);
+ result = (Node *) prm;
+ }
+ else if (node->parParam == NIL && slink->subLinkType == MULTIEXPR_SUBLINK)
{
List *newoper = NIL;
int i = 0;
@@ -202,6 +235,7 @@ make_subplan(SubLink *slink)
prm->paramkind = PARAM_EXEC;
prm->paramid = (AttrNumber) new_param(var, PlannerQueryLevel);
prm->paramtype = var->vartype;
+ pfree(var); /* var is only needed for new_param */
Assert(IsA(oper, Oper));
tup = get_operator_tuple(oper->opno);
@@ -219,7 +253,6 @@ make_subplan(SubLink *slink)
(Var *) left,
(Var *) right));
node->setParam = lappendi(node->setParam, prm->paramid);
- pfree(var);
i++;
}
slink->oper = newoper;
@@ -231,19 +264,6 @@ make_subplan(SubLink *slink)
else
result = (Node *) lfirst(newoper);
}
- else if (node->parParam == NULL && slink->subLinkType == EXISTS_SUBLINK)
- {
- Var *var = makeVar(0, 0, BOOLOID, -1, 0);
- Param *prm = makeNode(Param);
-
- prm->paramkind = PARAM_EXEC;
- prm->paramid = (AttrNumber) new_param(var, PlannerQueryLevel);
- prm->paramtype = var->vartype;
- node->setParam = lappendi(node->setParam, prm->paramid);
- pfree(var);
- PlannerInitPlan = lappend(PlannerInitPlan, node);
- result = (Node *) prm;
- }
else
{
/* make expression of SUBPLAN type */
@@ -333,7 +353,8 @@ set_unioni(List *l1, List *l2)
/*
* finalize_primnode: build lists of subplans and params appearing
- * in the given expression tree.
+ * in the given expression tree. NOTE: items are added to lists passed in,
+ * so caller must initialize lists to NIL before first call!
*/
typedef struct finalize_primnode_results {
@@ -341,20 +362,8 @@ typedef struct finalize_primnode_results {
List *paramids; /* List of PARAM_EXEC paramids found */
} finalize_primnode_results;
-static bool finalize_primnode_walker(Node *node,
- finalize_primnode_results *results);
-
-static void
-finalize_primnode(Node *expr, finalize_primnode_results *results)
-{
- results->subplans = NIL; /* initialize */
- results->paramids = NIL;
- (void) finalize_primnode_walker(expr, results);
-}
-
static bool
-finalize_primnode_walker(Node *node,
- finalize_primnode_results *results)
+finalize_primnode(Node *node, finalize_primnode_results *results)
{
if (node == NULL)
return false;
@@ -389,7 +398,7 @@ finalize_primnode_walker(Node *node,
}
/* fall through to recurse into subplan args */
}
- return expression_tree_walker(node, finalize_primnode_walker,
+ return expression_tree_walker(node, finalize_primnode,
(void *) results);
}
@@ -443,7 +452,7 @@ process_sublinks_mutator(Node *node, void *context)
{
SubLink *sublink = (SubLink *) node;
- /* First, scan the lefthand-side expressions.
+ /* First, scan the lefthand-side expressions, if any.
* This is a tad klugy since we modify the input SubLink node,
* but that should be OK (make_subplan does it too!)
*/
@@ -475,23 +484,28 @@ SS_finalize_plan(Plan *plan)
List *lst;
if (plan == NULL)
- return NULL;
+ return NIL;
- /* Find params in targetlist, make sure there are no subplans there */
+ results.subplans = NIL; /* initialize lists to NIL */
+ results.paramids = NIL;
+ /*
+ * When we call finalize_primnode, results.paramids lists are
+ * automatically merged together. But when recursing to self,
+ * we have to do it the hard way. We want the paramids list
+ * to include params in subplans as well as at this level.
+ * (We don't care about finding subplans of subplans, though.)
+ */
+
+ /* Find params and subplans in targetlist and qual */
finalize_primnode((Node *) plan->targetlist, &results);
- Assert(results.subplans == NIL);
+ finalize_primnode((Node *) plan->qual, &results);
- /* From here on, we invoke finalize_primnode_walker not finalize_primnode,
- * so that results.paramids lists are automatically merged together and
- * we don't have to do it the hard way. But when recursing to self,
- * we do have to merge the lists. Oh well.
- */
+ /* Check additional node-type-specific fields */
switch (nodeTag(plan))
{
case T_Result:
- finalize_primnode_walker(((Result *) plan)->resconstantqual,
- &results);
- /* results.subplans is NOT necessarily empty here ... */
+ finalize_primnode(((Result *) plan)->resconstantqual,
+ &results);
break;
case T_Append:
@@ -501,33 +515,26 @@ SS_finalize_plan(Plan *plan)
break;
case T_IndexScan:
- finalize_primnode_walker((Node *) ((IndexScan *) plan)->indxqual,
- &results);
- Assert(results.subplans == NIL);
+ finalize_primnode((Node *) ((IndexScan *) plan)->indxqual,
+ &results);
break;
case T_MergeJoin:
- finalize_primnode_walker((Node *) ((MergeJoin *) plan)->mergeclauses,
- &results);
- Assert(results.subplans == NIL);
+ finalize_primnode((Node *) ((MergeJoin *) plan)->mergeclauses,
+ &results);
break;
case T_HashJoin:
- finalize_primnode_walker((Node *) ((HashJoin *) plan)->hashclauses,
- &results);
- Assert(results.subplans == NIL);
+ finalize_primnode((Node *) ((HashJoin *) plan)->hashclauses,
+ &results);
break;
case T_Hash:
- finalize_primnode_walker((Node *) ((Hash *) plan)->hashkey,
- &results);
- Assert(results.subplans == NIL);
+ finalize_primnode((Node *) ((Hash *) plan)->hashkey,
+ &results);
break;
case T_Agg:
- /* XXX Code used to reject subplans in Aggref args; needed?? */
- break;
-
case T_SeqScan:
case T_NestLoop:
case T_Material:
@@ -539,12 +546,9 @@ SS_finalize_plan(Plan *plan)
default:
elog(ERROR, "SS_finalize_plan: node %d unsupported",
nodeTag(plan));
- return NULL;
}
- finalize_primnode_walker((Node *) plan->qual, &results);
- /* subplans are OK in the qual... */
-
+ /* Process left and right subplans, if any */
results.paramids = set_unioni(results.paramids,
SS_finalize_plan(plan->lefttree));
results.paramids = set_unioni(results.paramids,
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-24 17:19:53 +0000