Rewriter and planner should use only resno, not resname, to identify

target columns in INSERT and UPDATE targetlists.  Don't rely on resname
to be accurate in ruleutils, either.  This fixes bug reported by
Donald Fraser, in which renaming a column referenced in a rule did not
work very well.

1 files changed, 28 insertions, 40 deletions

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 49cc73f24e4..83989292d6a 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3,7 +3,7 @@
  *				back to source text
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.150 2003/08/08 21:42:09 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.151 2003/08/11 23:04:49 tgl Exp $
  *
  *	  This software is copyrighted by Jan Wieck - Hamburg.
  *
@@ -207,7 +207,6 @@ static char *generate_relation_name(Oid relid);
 static char *generate_function_name(Oid funcid, int nargs, Oid *argtypes);
 static char *generate_operator_name(Oid operid, Oid arg1, Oid arg2);
 static void print_operator_name(StringInfo buf, List *opname);
-static char *get_relid_attribute_name(Oid relid, AttrNumber attnum);
 
 #define only_marker(rte)  ((rte)->inh ? "" : "ONLY ")
 
@@ -1140,7 +1139,7 @@ decompile_column_index_array(Datum column_index_array, Oid relId,
 	{
 		char	   *colName;
 
-		colName = get_attname(relId, DatumGetInt16(keys[j]));
+		colName = get_relid_attribute_name(relId, DatumGetInt16(keys[j]));
 
 		if (j == 0)
 			appendStringInfo(buf, "%s",
@@ -1901,7 +1900,6 @@ get_basic_select_query(Query *query, deparse_context *context,
 	foreach(l, query->targetList)
 	{
 		TargetEntry *tle = (TargetEntry *) lfirst(l);
-		bool		tell_as = false;
 		char	   *colname;
 
 		if (tle->resdom->resjunk)
@@ -1924,24 +1922,30 @@ get_basic_select_query(Query *query, deparse_context *context,
 		else
 			colname = tle->resdom->resname;
 
-		/* Check if we must say AS ... */
-		if (!IsA(tle->expr, Var))
-			tell_as = (strcmp(colname, "?column?") != 0);
-		else
+		if (colname)			/* resname could be NULL */
 		{
-			Var		   *var = (Var *) (tle->expr);
-			char	   *schemaname;
-			char	   *refname;
-			char	   *attname;
+			/* Check if we must say AS ... */
+			bool		tell_as;
 
-			get_names_for_var(var, context, &schemaname, &refname, &attname);
-			tell_as = (attname == NULL ||
-					   strcmp(attname, colname) != 0);
-		}
+			if (!IsA(tle->expr, Var))
+				tell_as = (strcmp(colname, "?column?") != 0);
+			else
+			{
+				Var		   *var = (Var *) (tle->expr);
+				char	   *schemaname;
+				char	   *refname;
+				char	   *attname;
 
-		/* and do if so */
-		if (tell_as)
-			appendStringInfo(buf, " AS %s", quote_identifier(colname));
+				get_names_for_var(var, context,
+								  &schemaname, &refname, &attname);
+				tell_as = (attname == NULL ||
+						   strcmp(attname, colname) != 0);
+			}
+
+			/* and do if so */
+			if (tell_as)
+				appendStringInfo(buf, " AS %s", quote_identifier(colname));
+		}
 	}
 
 	/* Add the FROM clause if needed */
@@ -2151,7 +2155,9 @@ get_insert_query_def(Query *query, deparse_context *context)
 
 		appendStringInfo(buf, sep);
 		sep = ", ";
-		appendStringInfo(buf, "%s", quote_identifier(tle->resdom->resname));
+		appendStringInfo(buf, "%s",
+						 quote_identifier(get_relid_attribute_name(rte->relid,
+														tle->resdom->resno)));
 	}
 	appendStringInfo(buf, ") ");
 
@@ -2225,7 +2231,8 @@ get_update_query_def(Query *query, deparse_context *context)
 		 */
 		if (!tleIsArrayAssign(tle))
 			appendStringInfo(buf, "%s = ",
-							 quote_identifier(tle->resdom->resname));
+						quote_identifier(get_relid_attribute_name(rte->relid,
+														tle->resdom->resno)));
 		get_rule_expr((Node *) tle->expr, context, false);
 	}
 
@@ -4351,22 +4358,3 @@ print_operator_name(StringInfo buf, List *opname)
 		appendStringInfo(buf, "%s)", strVal(lfirst(opname)));
 	}
 }
-
-/*
- * get_relid_attribute_name
- *		Get an attribute name by its relations Oid and its attnum
- *
- * Same as underlying syscache routine get_attname(), except that error
- * is handled by elog() instead of returning NULL.
- */
-static char *
-get_relid_attribute_name(Oid relid, AttrNumber attnum)
-{
-	char	   *attname;
-
-	attname = get_attname(relid, attnum);
-	if (attname == NULL)
-		elog(ERROR, "cache lookup failed for attribute %d of relation %u",
-			 attnum, relid);
-	return attname;
-}