*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.20 1998/07/09 14:34:05 thomas Exp $
+ * $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.21 1998/07/14 03:51:42 thomas Exp $
*
*-------------------------------------------------------------------------
*/
Oid otype;
otype = ((TargetEntry *)lfirst(prev_target))->resdom->restype;
itype = ((TargetEntry *)lfirst(next_target))->resdom->restype;
- if (itype != otype)
+
+#ifdef PARSEDEBUG
+printf("transformUnionClause: types are %d -> %d\n", itype, otype);
+#endif
+
+ /* one or both is a NULL column? then don't convert... */
+ if (otype == InvalidOid)
+ {
+ /* propagate a known type forward, if available */
+ if (itype != InvalidOid)
+ {
+ ((TargetEntry *)lfirst(prev_target))->resdom->restype = itype;
+ }
+ }
+ else if (itype == InvalidOid)
+ {
+ }
+ /* they don't match in type? then convert... */
+ else if (itype != otype)
{
Node *expr;
((TargetEntry *)lfirst(next_target))->expr = expr;
((TargetEntry *)lfirst(next_target))->resdom->restype = otype;
}
+
/* both are UNKNOWN? then evaluate as text... */
else if (itype == UNKNOWNOID)
{