Index: src/backend/access/nbtree/nbtinsert.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v
retrieving revision 1.131
diff -c -r1.131 nbtinsert.c
*** src/backend/access/nbtree/nbtinsert.c	17 Jan 2006 00:09:00 -0000	1.131
--- src/backend/access/nbtree/nbtinsert.c	2 Feb 2006 20:05:47 -0000
***************
*** 121,127 ****
  	{
  		TransactionId xwait;
  
! 		xwait = _bt_check_unique(rel, btitem, heapRel, buf, itup_scankey);
  
  		if (TransactionIdIsValid(xwait))
  		{
--- 121,139 ----
  	{
  		TransactionId xwait;
  
! 		PG_TRY();
! 		{
! 			xwait = _bt_check_unique(rel, btitem, heapRel, buf, itup_scankey);
! 		}
! 		PG_CATCH();
! 		{
! 			_bt_freestack(stack);
! 			_bt_freeskey(itup_scankey);
! 			HOLD_INTERRUPTS();
! 			_bt_wrtbuf(rel, buf);
! 			PG_RE_THROW();
! 		}
! 		PG_END_TRY();
  
  		if (TransactionIdIsValid(xwait))
  		{
***************
*** 240,245 ****
--- 252,259 ----
  						return xwait;
  					}
  
+ 					if (nbuf != InvalidBuffer)
+ 						ReleaseBuffer(nbuf);
  					/*
  					 * Otherwise we have a definite conflict.
  					 */
Index: src/backend/commands/copy.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/commands/copy.c,v
retrieving revision 1.257
diff -c -r1.257 copy.c
*** src/backend/commands/copy.c	28 Dec 2005 03:25:32 -0000	1.257
--- src/backend/commands/copy.c	2 Feb 2006 20:05:47 -0000
***************
*** 1968,1973 ****
--- 1968,1975 ----
  
  		if (!skip_tuple)
  		{
+ 			bool trapped = false;
+ 
  			/* Place tuple in tuple slot */
  			ExecStoreTuple(tuple, slot, InvalidBuffer, false);
  
***************
*** 1979,1988 ****
  			simple_heap_insert(cstate->rel, tuple);
  
  			if (resultRelInfo->ri_NumIndices > 0)
! 				ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
  
  			/* AFTER ROW INSERT Triggers */
! 			ExecARInsertTriggers(estate, resultRelInfo, tuple);
  		}
  	}
  
--- 1981,2022 ----
  			simple_heap_insert(cstate->rel, tuple);
  
  			if (resultRelInfo->ri_NumIndices > 0)
! 			{
! 				MemoryContext curr = CurrentMemoryContext;
! 				PG_TRY();
! 				{
! 					ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
! 				}
! 				PG_CATCH();
! 				{
! 					trapped = true;
! 					MemoryContextSwitchTo(curr);
! 				}
! 				PG_END_TRY();
! 
! 				if (trapped)
! 				{
! 					ErrorData *ed;
! 					TransactionId xid;
! 					ItemPointerData tid;
! 
! 					ed = CopyErrorData();
! 					FlushErrorState();
! 					if (ed->sqlerrcode != ERRCODE_UNIQUE_VIOLATION)
! 						ReThrowError(ed);
! 
! 					FreeErrorData(ed);
! 					heap_delete(cstate->rel,
! 							&(tuple->t_self), &tid, &xid,
! 							GetCurrentCommandId() + 1,
! 							InvalidSnapshot,
! 							true);
! 				}
! 			}
  
  			/* AFTER ROW INSERT Triggers */
! 			if (!trapped)
! 				ExecARInsertTriggers(estate, resultRelInfo, tuple);
  		}
  	}
  
Index: src/backend/executor/execMain.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/executor/execMain.c,v
retrieving revision 1.265
diff -c -r1.265 execMain.c
*** src/backend/executor/execMain.c	12 Jan 2006 21:48:53 -0000	1.265
--- src/backend/executor/execMain.c	2 Feb 2006 20:05:47 -0000
***************
*** 1444,1453 ****
  	 * insert index entries for tuple
  	 */
  	if (resultRelInfo->ri_NumIndices > 0)
! 		ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
  
! 	/* AFTER ROW INSERT Triggers */
! 	ExecARInsertTriggers(estate, resultRelInfo, tuple);
  }
  
  /* ----------------------------------------------------------------
--- 1444,1494 ----
  	 * insert index entries for tuple
  	 */
  	if (resultRelInfo->ri_NumIndices > 0)
! 	{
! 		bool trapped_tuple = false;
! 		MemoryContext curr = CurrentMemoryContext;
! 
! 		PG_TRY();
! 		{
! 			ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
! 		}
! 		PG_CATCH();
! 		{
! 			trapped_tuple = true;
! 			MemoryContextSwitchTo(curr);
! 		}
! 		PG_END_TRY();
! 
! 		if (trapped_tuple)
! 		{
! 			ErrorData *ed;
! 			TransactionId xid;
! 			ItemPointerData tid = {{0, 0}, 0};
! 
! 			ed = CopyErrorData();
! 			FlushErrorState();
! 			if (ed->sqlerrcode != ERRCODE_UNIQUE_VIOLATION)
! 				ReThrowError(ed);
! 
! 			FreeErrorData(ed);
! 			(estate->es_processed)--;
! 			estate->es_lastoid = InvalidOid;
! 			setLastTid(&tid);
! 
! 			heap_delete(resultRelationDesc,
! 				&(tuple->t_self), &tid, &xid,
! 				estate->es_snapshot->curcid + 1,
! 				estate->es_crosscheck_snapshot,
! 				true);
! 			CommandCounterIncrement();
! 		}
  
! 		if (!trapped_tuple)
! 		{
! 			/* AFTER ROW INSERT Triggers */
! 			ExecARInsertTriggers(estate, resultRelInfo, tuple);
! 		}
! 	}
  }
  
  /* ----------------------------------------------------------------
Index: src/backend/parser/gram.y
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/parser/gram.y,v
retrieving revision 2.521
diff -c -r2.521 gram.y
*** src/backend/parser/gram.y	29 Dec 2005 04:53:18 -0000	2.521
--- src/backend/parser/gram.y	2 Feb 2006 20:05:48 -0000
***************
*** 230,235 ****
--- 230,237 ----
  				prep_type_clause prep_type_list
  				execute_param_clause using_clause
  
+ %type <list>	insert_unless insert_unless_constraints
+ 
  %type <range>	into_clause OptTempTableName
  
  %type <defelt>	createfunc_opt_item common_func_opt_item
***************
*** 406,415 ****
  	TRUNCATE TRUSTED TYPE_P
  
  	UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNTIL
! 	UPDATE USER USING
  
  	VACUUM VALID VALIDATOR VALUES VARCHAR VARYING
! 	VERBOSE VIEW VOLATILE
  
  	WHEN WHERE WITH WITHOUT WORK WRITE
  
--- 408,417 ----
  	TRUNCATE TRUSTED TYPE_P
  
  	UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNTIL
! 	UNLESS UPDATE USER USING
  
  	VACUUM VALID VALIDATOR VALUES VARCHAR VARYING
! 	VERBOSE VIEW VIOLATION VOLATILE
  
  	WHEN WHERE WITH WITHOUT WORK WRITE
  
***************
*** 5071,5080 ****
   *****************************************************************************/
  
  InsertStmt:
! 			INSERT INTO qualified_name insert_rest
  				{
! 					$4->relation = $3;
! 					$$ = (Node *) $4;
  				}
  		;
  
--- 5073,5099 ----
   *****************************************************************************/
  
  InsertStmt:
! 			INSERT INTO qualified_name insert_unless insert_rest
! 				{
! 					$5->relation = $3;
! 					$5->unless = $4;
! 					$$ = (Node *) $5;
! 				}
! 		;
! 
! insert_unless:
! 			UNLESS CONSTRAINT VIOLATION ON insert_unless_constraints
  				{
! 					$$ = $5;
! 				}
! 			| /* empty */
! 				{ $$ = NIL; }
! 		;
! 
! insert_unless_constraints:
! 			'(' constraints_set_list ')'
! 				{
! 					$$ = $2;
  				}
  		;
  
***************
*** 8315,8320 ****
--- 8334,8340 ----
  			| UNCOMMITTED
  			| UNENCRYPTED
  			| UNKNOWN
+ 			| UNLESS
  			| UNLISTEN
  			| UNTIL
  			| UPDATE
***************
*** 8324,8329 ****
--- 8344,8350 ----
  			| VALUES
  			| VARYING
  			| VIEW
+ 			| VIOLATION
  			| VOLATILE
  			| WITH
  			| WITHOUT
Index: src/backend/parser/keywords.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/parser/keywords.c,v
retrieving revision 1.170
diff -c -r1.170 keywords.c
*** src/backend/parser/keywords.c	27 Dec 2005 04:00:07 -0000	1.170
--- src/backend/parser/keywords.c	2 Feb 2006 20:05:48 -0000
***************
*** 345,350 ****
--- 345,351 ----
  	{"union", UNION},
  	{"unique", UNIQUE},
  	{"unknown", UNKNOWN},
+ 	{"unless", UNLESS},
  	{"unlisten", UNLISTEN},
  	{"until", UNTIL},
  	{"update", UPDATE},
***************
*** 358,363 ****
--- 359,365 ----
  	{"varying", VARYING},
  	{"verbose", VERBOSE},
  	{"view", VIEW},
+ 	{"violation", VIOLATION},
  	{"volatile", VOLATILE},
  	{"when", WHEN},
  	{"where", WHERE},
Index: src/include/nodes/parsenodes.h
===================================================================
RCS file: /projects/cvsroot/pgsql/src/include/nodes/parsenodes.h,v
retrieving revision 1.298
diff -c -r1.298 parsenodes.h
*** src/include/nodes/parsenodes.h	7 Dec 2005 15:20:55 -0000	1.298
--- src/include/nodes/parsenodes.h	2 Feb 2006 20:05:48 -0000
***************
*** 602,607 ****
--- 602,608 ----
  	NodeTag		type;
  	RangeVar   *relation;		/* relation to insert into */
  	List	   *cols;			/* optional: names of the target columns */
+ 	List	*unless;			/* optional: names of indexes to avoid */
  
  	/*
  	 * An INSERT statement has *either* VALUES or SELECT, never both. If