I have modifed heap.c so that it won't automatically generate duplicate

constraint names.

> > A reasonable interpretation of DROP CONSTRAINT "foo" is to drop *all*
> > constraints named "foo" on the target table.
>
> Then it should probably be a good thing to avoid the automatic
> generation of
> duplicate names?  I might take a look at that, actually...
>

Christopher Kings-Lynne

diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 03f16e11c3f3710b2589d8e7330bfd0a2bb386b8..ec14a736965b4aa27b6af2596fca1a849c897704 100644 (file)
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.163 2001/05/07 00:43:17 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.164 2001/05/09 21:13:35 momjian Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1832,8 +1832,47 @@ AddRelationRawConstraints(Relation rel,
        }
        else
        {
+           int         i;
+           int         j;
+           bool            success;
+           List       *listptr2;
            ccname = (char *) palloc(NAMEDATALEN);
-           snprintf(ccname, NAMEDATALEN, "$%d", numchecks + 1);
+
+           /* Loop until we find a non-conflicting constraint name */
+           /* What happens if this loops forever? */
+           j = numchecks + 1;
+           do {
+               success = true;
+               snprintf(ccname, NAMEDATALEN, "$%d", j);
+
+               /* Check against old constraints */
+               for (i = 0; i < numoldchecks; i++)
+               {
+                   if (strcmp(oldchecks[i].ccname, ccname) == 0) {
+                       success = false;
+                       break;
+                   }
+               }
+               /* Check against other new constraints, if the check hasn't already failed */
+               if (success) {
+                   foreach(listptr2, rawConstraints)
+                   {
+                       Constraint *cdef2 = (Constraint *) lfirst(listptr2);
+       
+                       if (cdef2 == cdef ||
+                           cdef2->contype != CONSTR_CHECK ||
+                           cdef2->raw_expr == NULL ||
+                           cdef2->name == NULL)
+                           continue;
+                       if (strcmp(cdef2->name, ccname) == 0) {
+                           success = false;
+                           break;
+                       }
+                   }
+               }
+
+               ++j;
+           } while (!success);
        }
 
        /*