Split the processing of INSERT/UPDATE/DELETE operations out of execMain.c.

They are now handled by a new plan node type called ModifyTable, which is
placed at the top of the plan tree.  In itself this change doesn't do much,
except perhaps make the handling of RETURNING lists and inherited UPDATEs a
tad less klugy.  But it is necessary preparation for the intended extension of
allowing RETURNING queries inside WITH.

Marko Tiikkaja

2 files changed, 52 insertions, 12 deletions

diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index ef3d9beb062..048d12f97a2 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994-5, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.190 2009/08/22 02:06:32 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.191 2009/10/10 01:43:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -581,6 +581,7 @@ ExplainNode(Plan *plan, PlanState *planstate,
 	const char *pname;			/* node type name for text output */
 	const char *sname;			/* node type name for non-text output */
 	const char *strategy = NULL;
+	const char *operation = NULL;
 	int			save_indent = es->indent;
 	bool		haschildren;
 
@@ -591,6 +592,24 @@ ExplainNode(Plan *plan, PlanState *planstate,
 		case T_Result:
 			pname = sname = "Result";
 			break;
+		case T_ModifyTable:
+			sname = "ModifyTable";
+			switch (((ModifyTable *) plan)->operation)
+			{
+				case CMD_INSERT:
+					pname = operation = "Insert";
+					break;
+				case CMD_UPDATE:
+					pname = operation = "Update";
+					break;
+				case CMD_DELETE:
+					pname = operation = "Delete";
+					break;
+				default:
+					pname = "???";
+					break;
+			}
+			break;
 		case T_Append:
 			pname = sname = "Append";
 			break;
@@ -736,6 +755,8 @@ ExplainNode(Plan *plan, PlanState *planstate,
 		ExplainPropertyText("Node Type", sname, es);
 		if (strategy)
 			ExplainPropertyText("Strategy", strategy, es);
+		if (operation)
+			ExplainPropertyText("Operation", operation, es);
 		if (relationship)
 			ExplainPropertyText("Parent Relationship", relationship, es);
 		if (plan_name)
@@ -1023,6 +1044,7 @@ ExplainNode(Plan *plan, PlanState *planstate,
 	haschildren = plan->initPlan ||
 		outerPlan(plan) ||
 		innerPlan(plan) ||
+		IsA(plan, ModifyTable) ||
 		IsA(plan, Append) ||
 		IsA(plan, BitmapAnd) ||
 		IsA(plan, BitmapOr) ||
@@ -1059,6 +1081,11 @@ ExplainNode(Plan *plan, PlanState *planstate,
 	/* special child plans */
 	switch (nodeTag(plan))
 	{
+		case T_ModifyTable:
+			ExplainMemberNodes(((ModifyTable *) plan)->plans,
+							   ((ModifyTableState *) planstate)->mt_plans,
+							   outer_plan, es);
+			break;
 		case T_Append:
 			ExplainMemberNodes(((Append *) plan)->appendplans,
 							   ((AppendState *) planstate)->appendplans,
@@ -1408,7 +1435,8 @@ ExplainScanTarget(Scan *plan, ExplainState *es)
 }
 
 /*
- * Explain the constituent plans of an Append, BitmapAnd, or BitmapOr node.
+ * Explain the constituent plans of a ModifyTable, Append, BitmapAnd,
+ * or BitmapOr node.
  *
  * Ordinarily we don't pass down outer_plan to our child nodes, but in these
  * cases we must, since the node could be an "inner indexscan" in which case
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index c1f55cfcf93..47cf0c470d6 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.252 2009/08/04 16:08:36 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.253 2009/10/10 01:43:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -55,6 +55,7 @@ int			SessionReplicationRole = SESSION_REPLICATION_ROLE_ORIGIN;
 static void ConvertTriggerToFK(CreateTrigStmt *stmt, Oid funcoid);
 static void InsertTrigger(TriggerDesc *trigdesc, Trigger *trigger, int indx);
 static HeapTuple GetTupleForTrigger(EState *estate,
+				   PlanState *subplanstate,
 				   ResultRelInfo *relinfo,
 				   ItemPointer tid,
 				   TupleTableSlot **newSlot);
@@ -1793,7 +1794,8 @@ ExecASDeleteTriggers(EState *estate, ResultRelInfo *relinfo)
 }
 
 bool
-ExecBRDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
+ExecBRDeleteTriggers(EState *estate, PlanState *subplanstate,
+					 ResultRelInfo *relinfo,
 					 ItemPointer tupleid)
 {
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
@@ -1806,7 +1808,8 @@ ExecBRDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
 	TupleTableSlot *newSlot;
 	int			i;
 
-	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, &newSlot);
+	trigtuple = GetTupleForTrigger(estate, subplanstate, relinfo, tupleid,
+								   &newSlot);
 	if (trigtuple == NULL)
 		return false;
 
@@ -1862,7 +1865,7 @@ ExecARDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
 
 	if (trigdesc && trigdesc->n_after_row[TRIGGER_EVENT_DELETE] > 0)
 	{
-		HeapTuple	trigtuple = GetTupleForTrigger(estate, relinfo,
+		HeapTuple	trigtuple = GetTupleForTrigger(estate, NULL, relinfo,
 												   tupleid, NULL);
 
 		AfterTriggerSaveEvent(relinfo, TRIGGER_EVENT_DELETE,
@@ -1941,7 +1944,8 @@ ExecASUpdateTriggers(EState *estate, ResultRelInfo *relinfo)
 }
 
 HeapTuple
-ExecBRUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
+ExecBRUpdateTriggers(EState *estate, PlanState *subplanstate,
+					 ResultRelInfo *relinfo,
 					 ItemPointer tupleid, HeapTuple newtuple)
 {
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
@@ -1954,16 +1958,18 @@ ExecBRUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 	TupleTableSlot *newSlot;
 	int			i;
 
-	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, &newSlot);
+	trigtuple = GetTupleForTrigger(estate, subplanstate, relinfo, tupleid,
+								   &newSlot);
 	if (trigtuple == NULL)
 		return NULL;
 
 	/*
 	 * In READ COMMITTED isolation level it's possible that newtuple was
-	 * changed due to concurrent update.
+	 * changed due to concurrent update.  In that case we have a raw subplan
+	 * output tuple and need to run it through the junk filter.
 	 */
 	if (newSlot != NULL)
-		intuple = newtuple = ExecRemoveJunk(estate->es_junkFilter, newSlot);
+		intuple = newtuple = ExecRemoveJunk(relinfo->ri_junkFilter, newSlot);
 
 	LocTriggerData.type = T_TriggerData;
 	LocTriggerData.tg_event = TRIGGER_EVENT_UPDATE |
@@ -2014,7 +2020,7 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 
 	if (trigdesc && trigdesc->n_after_row[TRIGGER_EVENT_UPDATE] > 0)
 	{
-		HeapTuple	trigtuple = GetTupleForTrigger(estate, relinfo,
+		HeapTuple	trigtuple = GetTupleForTrigger(estate, NULL, relinfo,
 												   tupleid, NULL);
 
 		AfterTriggerSaveEvent(relinfo, TRIGGER_EVENT_UPDATE,
@@ -2094,7 +2100,9 @@ ExecASTruncateTriggers(EState *estate, ResultRelInfo *relinfo)
 
 
 static HeapTuple
-GetTupleForTrigger(EState *estate, ResultRelInfo *relinfo,
+GetTupleForTrigger(EState *estate,
+				   PlanState *subplanstate,
+				   ResultRelInfo *relinfo,
 				   ItemPointer tid,
 				   TupleTableSlot **newSlot)
 {
@@ -2111,6 +2119,9 @@ GetTupleForTrigger(EState *estate, ResultRelInfo *relinfo,
 
 		*newSlot = NULL;
 
+		/* caller must pass a subplanstate if EvalPlanQual is possible */
+		Assert(subplanstate != NULL);
+
 		/*
 		 * lock tuple for update
 		 */
@@ -2143,6 +2154,7 @@ ltrmark:;
 
 					epqslot = EvalPlanQual(estate,
 										   relinfo->ri_RangeTableIndex,
+										   subplanstate,
 										   &update_ctid,
 										   update_xmax);
 					if (!TupIsNull(epqslot))