*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/prep/prepunion.c,v 1.68 2001/10/28 06:25:46 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/prep/prepunion.c,v 1.69 2001/11/12 20:04:20 tgl Exp $
*
*-------------------------------------------------------------------------
*/
bool hack_constants,
List *input_tlist,
List *refnames_tlist);
+static void merge_tlist_typmods(List *tlist, List *planlist);
static bool tlist_same_datatypes(List *tlist, List *colTypes, bool junkOK);
static Node *adjust_inherited_attrs_mutator(Node *node,
adjust_inherited_attrs_context *context);
List *refnames_tlist)
{
List *planlist;
+ List *tlist;
Plan *plan;
/*
op, refnames_tlist));
/*
- * Append the child results together.
+ * Generate tlist for Append plan node.
*
* The tlist for an Append plan isn't important as far as the Append is
* concerned, but we must make it look real anyway for the benefit of
* the next plan level up.
*/
- plan = (Plan *)
- make_append(planlist,
- false,
- generate_setop_tlist(op->colTypes, -1, false,
+ tlist = generate_setop_tlist(op->colTypes, -1, false,
((Plan *) lfirst(planlist))->targetlist,
- refnames_tlist));
+ refnames_tlist);
+ merge_tlist_typmods(tlist, planlist);
+
+ /*
+ * Append the child results together.
+ */
+ plan = (Plan *) make_append(planlist, false, tlist);
/*
* For UNION ALL, we just need the Append plan. For UNION, need to
*/
if (!op->all)
{
- List *tlist,
- *sortList;
+ List *sortList;
- tlist = new_unsorted_tlist(plan->targetlist);
+ tlist = new_unsorted_tlist(tlist);
sortList = addAllTargetsToSortList(NIL, tlist);
plan = make_sortplan(parse, tlist, plan, sortList);
plan = (Plan *) make_unique(tlist, plan, copyObject(sortList));
*rplan,
*plan;
List *tlist,
- *sortList;
+ *sortList,
+ *planlist;
SetOpCmd cmd;
/* Recurse on children, ensuring their outputs are marked */
rplan = recurse_set_operations(op->rarg, parse,
op->colTypes, false, 1,
refnames_tlist);
+ planlist = makeList2(lplan, rplan);
/*
- * Append the child results together.
+ * Generate tlist for Append plan node.
*
* The tlist for an Append plan isn't important as far as the Append is
* concerned, but we must make it look real anyway for the benefit of
* flag column is shown as a variable not a constant, else setrefs.c
* will get confused.
*/
- plan = (Plan *)
- make_append(makeList2(lplan, rplan),
- false,
- generate_setop_tlist(op->colTypes, 2, false,
- lplan->targetlist,
- refnames_tlist));
+ tlist = generate_setop_tlist(op->colTypes, 2, false,
+ lplan->targetlist,
+ refnames_tlist);
+ merge_tlist_typmods(tlist, planlist);
+
+ /*
+ * Append the child results together.
+ */
+ plan = (Plan *) make_append(planlist, false, tlist);
/*
* Sort the child results, then add a SetOp plan node to generate the
* correct output.
*/
- tlist = new_unsorted_tlist(plan->targetlist);
+ tlist = new_unsorted_tlist(tlist);
sortList = addAllTargetsToSortList(NIL, tlist);
plan = make_sortplan(parse, tlist, plan, sortList);
switch (op->op)
{
/* Same UNION, so fold children into parent's subplan list */
return nconc(recurse_union_children(op->larg, parse,
- top_union, refnames_tlist),
+ top_union,
+ refnames_tlist),
recurse_union_children(op->rarg, parse,
- top_union, refnames_tlist));
+ top_union,
+ refnames_tlist));
}
}
Oid colType = (Oid) lfirsti(i);
TargetEntry *inputtle = (TargetEntry *) lfirst(input_tlist);
TargetEntry *reftle = (TargetEntry *) lfirst(refnames_tlist);
+ int32 colTypmod;
Assert(inputtle->resdom->resno == resno);
Assert(reftle->resdom->resno == resno);
* subquery-scan plans; we don't want phony constants appearing in
* the output tlists of upper-level nodes!
*/
- resdom = makeResdom((AttrNumber) resno++,
- colType,
- -1,
- pstrdup(reftle->resdom->resname),
- false);
if (hack_constants && inputtle->expr && IsA(inputtle->expr, Const))
expr = inputtle->expr;
else
inputtle->resdom->restype,
inputtle->resdom->restypmod,
0);
- expr = coerce_to_common_type(NULL,
- expr,
- colType,
- "UNION/INTERSECT/EXCEPT");
+ if (inputtle->resdom->restype == colType)
+ {
+ /* no coercion needed, and believe the input typmod */
+ colTypmod = inputtle->resdom->restypmod;
+ }
+ else
+ {
+ expr = coerce_to_common_type(NULL,
+ expr,
+ colType,
+ "UNION/INTERSECT/EXCEPT");
+ colTypmod = -1;
+ }
+ resdom = makeResdom((AttrNumber) resno++,
+ colType,
+ colTypmod,
+ pstrdup(reftle->resdom->resname),
+ false);
tlist = lappend(tlist, makeTargetEntry(resdom, expr));
input_tlist = lnext(input_tlist);
refnames_tlist = lnext(refnames_tlist);
}
/*
+ * Merge typmods of a list of set-operation subplans.
+ *
+ * If the inputs all agree on type and typmod of a particular column,
+ * use that typmod; else use -1. We assume the result tlist has been
+ * initialized with the types and typmods of the first input subplan.
+ */
+static void
+merge_tlist_typmods(List *tlist, List *planlist)
+{
+ List *planl;
+
+ foreach(planl, planlist)
+ {
+ Plan *subplan = (Plan *) lfirst(planl);
+ List *subtlist = subplan->targetlist;
+ List *restlist;
+
+ foreach(restlist, tlist)
+ {
+ TargetEntry *restle = (TargetEntry *) lfirst(restlist);
+ TargetEntry *subtle;
+
+ if (restle->resdom->resjunk)
+ continue;
+ Assert(subtlist != NIL);
+ subtle = (TargetEntry *) lfirst(subtlist);
+ while (subtle->resdom->resjunk)
+ {
+ subtlist = lnext(subtlist);
+ Assert(subtlist != NIL);
+ subtle = (TargetEntry *) lfirst(subtlist);
+ }
+ if (restle->resdom->restype != subtle->resdom->restype ||
+ restle->resdom->restypmod != subtle->resdom->restypmod)
+ restle->resdom->restypmod = -1;
+ subtlist = lnext(subtlist);
+ }
+ }
+}
+
+/*
* Does tlist have same datatypes as requested colTypes?
*
* Resjunk columns are ignored if junkOK is true; otherwise presence of
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