Commit of a *MAJOR* patch from Dan McGuirk <djm@indirect.com>

Changes:

        * Unique index capability works using the syntax 'create unique
          index'.

        * Duplicate OID's in the system tables are removed.  I put
          little scripts called 'duplicate_oids' and 'find_oid' in
          include/catalog that help to find and remove duplicate OID's.
          I also moved 'unused_oids' from backend/catalog to
          include/catalog, since it has to be in the same directory
          as the include files in order to work.

        * The backend tries converting the name of a function or aggregate
          to all lowercase if the original name given doesn't work (mostly
          for compatibility with ODBC).

        * You can 'SELECT NULL' to your heart's content.

        * I put my _bt_updateitem fix in instead, which uses
          _bt_insertonpg so that even if the new key is so big that
          the page has to be split, everything still works.

        * All literal references to system catalog OID's have been
          replaced with references to define'd constants from the catalog
          header files.

        * I added a couple of node copy functions.  I think this was a
          preliminary attempt to get rules to work.

src/backend/commands/defind.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/commands/Attic/defind.c,v 1.8 1996/11/06 08:21:33 scrappy Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/commands/Attic/defind.c,v 1.9 1996/11/13 20:48:22 scrappy Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -69,6 +69,7 @@ DefineIndex(char *heapRelationName,
 	    char *accessMethodName,
 	    List *attributeList,
 	    List *parameterList,
+	    bool unique,
 	    Expr *predicate,
 	    List *rangetable)
 {
@@ -176,7 +177,7 @@ DefineIndex(char *heapRelationName,
 		     &fInfo, NULL, accessMethodId, 
 		     numberOfAttributes, attributeNumberA,
 		     classObjectId, parameterCount, parameterA, (Node*)cnfPred,
-		     lossy);
+		     lossy, unique);
     }else {
 	attributeNumberA =
 	    (AttrNumber *)palloc(numberOfAttributes *
@@ -192,7 +193,7 @@ DefineIndex(char *heapRelationName,
 		     ((IndexElem*)lfirst(attributeList))->tname,
 		     accessMethodId, numberOfAttributes, attributeNumberA,
 		     classObjectId, parameterCount, parameterA, (Node*)cnfPred,
-		     lossy);
+		     lossy, unique);
     }
 }