Fix get_sort_group_operators() so that it doesn't think arrays can be grouped

via hashing.  Eventually we ought to make that possible, but it won't happen
for 8.4.  Per yesterday's report from Robert Haas.

diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
index b8555c46153b8d17c8b90c44dc8403c258f68c3f..16ed3a11ed5e8c4260f3a23e52c7a717ebd937d8 100644 (file)
--- a/src/backend/parser/parse_oper.c
+++ b/src/backend/parser/parse_oper.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/parser/parse_oper.c,v 1.108 2009/06/11 14:49:00 momjian Exp $
+ *   $PostgreSQL: pgsql/src/backend/parser/parse_oper.c,v 1.109 2009/06/13 15:42:09 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -203,7 +203,7 @@ get_sort_group_operators(Oid argtype,
     * If the datatype is an array, then we can use array_lt and friends ...
     * but only if there are suitable operators for the element type.  (This
     * check is not in the raw typcache.c code ... should it be?)  Testing all
-    * three operator IDs here should be redundant.
+    * three operator IDs here should be redundant, but let's do it anyway.
     */
    if (lt_opr == ARRAY_LT_OP ||
        eq_opr == ARRAY_EQ_OP ||
@@ -215,12 +215,31 @@ get_sort_group_operators(Oid argtype,
        {
            typentry = lookup_type_cache(elem_type,
                     TYPECACHE_LT_OPR | TYPECACHE_EQ_OPR | TYPECACHE_GT_OPR);
-           if (!OidIsValid(typentry->lt_opr))
-               lt_opr = InvalidOid;    /* element type has no "<" */
+#ifdef NOT_USED
+           /* We should do this ... */
            if (!OidIsValid(typentry->eq_opr))
-               eq_opr = InvalidOid;    /* element type has no "=" */
-           if (!OidIsValid(typentry->gt_opr))
-               gt_opr = InvalidOid;    /* element type has no ">" */
+           {
+               /* element type is neither sortable nor hashable */
+               lt_opr = eq_opr = gt_opr = InvalidOid;
+           }
+           else if (!OidIsValid(typentry->lt_opr) ||
+                    !OidIsValid(typentry->gt_opr))
+           {
+               /* element type is hashable but not sortable */
+               lt_opr = gt_opr = InvalidOid;
+           }
+#else
+           /*
+            * ... but for the moment we have to do this.  This is because
+            * anyarray has sorting but not hashing support.  So, if the
+            * element type is only hashable, there is nothing we can do
+            * with the array type.
+            */
+           if (!OidIsValid(typentry->lt_opr) ||
+               !OidIsValid(typentry->eq_opr) ||
+               !OidIsValid(typentry->gt_opr))
+               lt_opr = eq_opr = gt_opr = InvalidOid;  /* not sortable */
+#endif
        }
        else
            lt_opr = eq_opr = gt_opr = InvalidOid;      /* bogus array type? */