From c876d965f5e7a8b300f57d21de570cca291ac84a Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 30 Dec 2005 18:34:22 +0000
Subject: [PATCH] Repair EXPLAIN failure when trying to display a plan
condition that involves selection of a field from the result of a function
returning RECORD. I believe this case is new in 8.1; it's due to the addition
of OUT parameters. Per example from Michael Fuhr.
---
src/backend/utils/adt/ruleutils.c | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index eaf4f195077..7c47054633f 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3,7 +3,7 @@
* back to source text
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.211 2005/12/28 01:30:00 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.212 2005/12/30 18:34:22 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -1525,8 +1525,15 @@ deparse_context_for_subplan(const char *name, List *tlist,
attrs = lappend(attrs, makeString(pstrdup(buf)));
}
- rte->rtekind = RTE_SPECIAL; /* XXX */
+ /*
+ * We create an RTE_SPECIAL RangeTblEntry, and store the given tlist
+ * in its coldeflist field. This is a hack to make the tlist available
+ * to get_name_for_var_field(). RTE_SPECIAL nodes shouldn't appear in
+ * deparse contexts otherwise.
+ */
+ rte->rtekind = RTE_SPECIAL;
rte->relid = InvalidOid;
+ rte->coldeflist = tlist;
rte->eref = makeAlias(name, attrs);
rte->inh = false;
rte->inFromCl = true;
@@ -2571,7 +2578,8 @@ get_names_for_var(Var *var, int levelsup, deparse_context *context,
* Note: this has essentially the same logic as the parser's
* expandRecordVariable() function, but we are dealing with a different
* representation of the input context, and we only need one field name not
- * a TupleDesc.
+ * a TupleDesc. Also, we have a special case for RTE_SPECIAL so that we can
+ * deal with displaying RECORD-returning functions in subplan targetlists.
*/
static const char *
get_name_for_var_field(Var *var, int fieldno,
@@ -2602,7 +2610,6 @@ get_name_for_var_field(Var *var, int fieldno,
switch (rte->rtekind)
{
case RTE_RELATION:
- case RTE_SPECIAL:
/*
* This case should not occur: a column of a table shouldn't have
@@ -2663,6 +2670,21 @@ get_name_for_var_field(Var *var, int fieldno,
* its result columns as RECORD, which is not allowed.
*/
break;
+ case RTE_SPECIAL:
+ /*
+ * This case occurs during EXPLAIN when we are looking at a
+ * deparse context node set up by deparse_context_for_subplan().
+ * Look into the subplan's target list to get the referenced
+ * expression, and then pass it to get_expr_result_type().
+ */
+ if (rte->coldeflist)
+ {
+ TargetEntry *ste = get_tle_by_resno(rte->coldeflist, attnum);
+
+ if (ste != NULL)
+ expr = (Node *) ste->expr;
+ }
+ break;
}
/*
--
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