*** pgsql/src/backend/executor/execMain.c	2009/02/02 19:31:39	1.322
--- pgsql/src/backend/executor/execMain.c	2009/02/08 18:02:27	1.323
***************
*** 26,32 ****
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.321 2009/01/22 20:16:03 tgl Exp $
   *
   *-------------------------------------------------------------------------
   */
--- 26,32 ----
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.322 2009/02/02 19:31:39 alvherre Exp $
   *
   *-------------------------------------------------------------------------
   */
*************** ExecInsert(TupleTableSlot *slot,
*** 1766,1771 ****
--- 1766,1786 ----
  	resultRelInfo = estate->es_result_relation_info;
  	resultRelationDesc = resultRelInfo->ri_RelationDesc;
  
+ 	/*
+ 	 * If the result relation has OIDs, force the tuple's OID to zero so that
+ 	 * heap_insert will assign a fresh OID.  Usually the OID already will be
+ 	 * zero at this point, but there are corner cases where the plan tree can
+ 	 * return a tuple extracted literally from some table with the same
+ 	 * rowtype.
+ 	 *
+ 	 * XXX if we ever wanted to allow users to assign their own OIDs to new
+ 	 * rows, this'd be the place to do it.  For the moment, we make a point
+ 	 * of doing this before calling triggers, so that a user-supplied trigger
+ 	 * could hack the OID if desired.
+ 	 */
+ 	if (resultRelationDesc->rd_rel->relhasoids)
+ 		HeapTupleSetOid(tuple, InvalidOid);
+ 
  	/* BEFORE ROW INSERT Triggers */
  	if (resultRelInfo->ri_TrigDesc &&
  		resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_INSERT] > 0)
*************** intorel_receive(TupleTableSlot *slot, De
*** 3033,3038 ****
--- 3048,3059 ----
  	 */
  	tuple = ExecMaterializeSlot(slot);
  
+ 	/*
+ 	 * force assignment of new OID (see comments in ExecInsert)
+ 	 */
+ 	if (myState->rel->rd_rel->relhasoids)
+ 		HeapTupleSetOid(tuple, InvalidOid);
+ 
  	heap_insert(myState->rel,
  				tuple,
  				myState->estate->es_output_cid,