Extend the ExecInitNode API so that plan nodes receive a set of flag

bits indicating which optional capabilities can actually be exercised
at runtime.  This will allow Sort and Material nodes, and perhaps later
other nodes, to avoid unnecessary overhead in common cases.
This commit just adds the infrastructure and arranges to pass the correct
flag values down to plan nodes; none of the actual optimizations are here
yet.  I'm committing this separately in case anyone wants to measure the
added overhead.  (It should be negligible.)

Simon Riggs and Tom Lane

1 files changed, 54 insertions, 31 deletions

diff --git a/src/backend/executor/execProcnode.c b/src/backend/executor/execProcnode.c
index c8b8d419512..d7d3e541fa6 100644
--- a/src/backend/executor/execProcnode.c
+++ b/src/backend/executor/execProcnode.c
@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/execProcnode.c,v 1.52 2005/12/07 15:27:42 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execProcnode.c,v 1.53 2006/02/28 04:10:27 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -45,7 +45,7 @@
  *					DEPT		  EMP
  *				(name = "shoe")
  *
- *		ExecStart() is called first.
+ *		ExecutorStart() is called first.
  *		It calls InitPlan() which calls ExecInitNode() on
  *		the root of the plan -- the nest loop node.
  *
@@ -108,18 +108,19 @@
 /* ------------------------------------------------------------------------
  *		ExecInitNode
  *
- *		Recursively initializes all the nodes in the plan rooted
+ *		Recursively initializes all the nodes in the plan tree rooted
  *		at 'node'.
  *
- *		Initial States:
- *		  'node' is the plan produced by the query planner
- *		  'estate' is the shared execution state for the query tree
+ *		Inputs:
+ *		  'node' is the current node of the plan produced by the query planner
+ *		  'estate' is the shared execution state for the plan tree
+ *		  'eflags' is a bitwise OR of flag bits described in executor.h
  *
  *		Returns a PlanState node corresponding to the given Plan node.
  * ------------------------------------------------------------------------
  */
 PlanState *
-ExecInitNode(Plan *node, EState *estate)
+ExecInitNode(Plan *node, EState *estate, int eflags)
 {
 	PlanState  *result;
 	List	   *subps;
@@ -137,100 +138,122 @@ ExecInitNode(Plan *node, EState *estate)
 			 * control nodes
 			 */
 		case T_Result:
-			result = (PlanState *) ExecInitResult((Result *) node, estate);
+			result = (PlanState *) ExecInitResult((Result *) node,
+												  estate, eflags);
 			break;
 
 		case T_Append:
-			result = (PlanState *) ExecInitAppend((Append *) node, estate);
+			result = (PlanState *) ExecInitAppend((Append *) node,
+												  estate, eflags);
 			break;
 
 		case T_BitmapAnd:
-			result = (PlanState *) ExecInitBitmapAnd((BitmapAnd *) node, estate);
+			result = (PlanState *) ExecInitBitmapAnd((BitmapAnd *) node,
+													 estate, eflags);
 			break;
 
 		case T_BitmapOr:
-			result = (PlanState *) ExecInitBitmapOr((BitmapOr *) node, estate);
+			result = (PlanState *) ExecInitBitmapOr((BitmapOr *) node,
+													estate, eflags);
 			break;
 
 			/*
 			 * scan nodes
 			 */
 		case T_SeqScan:
-			result = (PlanState *) ExecInitSeqScan((SeqScan *) node, estate);
+			result = (PlanState *) ExecInitSeqScan((SeqScan *) node,
+												   estate, eflags);
 			break;
 
 		case T_IndexScan:
-			result = (PlanState *) ExecInitIndexScan((IndexScan *) node, estate);
+			result = (PlanState *) ExecInitIndexScan((IndexScan *) node,
+													 estate, eflags);
 			break;
 
 		case T_BitmapIndexScan:
-			result = (PlanState *) ExecInitBitmapIndexScan((BitmapIndexScan *) node, estate);
+			result = (PlanState *) ExecInitBitmapIndexScan((BitmapIndexScan *) node,
+														   estate, eflags);
 			break;
 
 		case T_BitmapHeapScan:
-			result = (PlanState *) ExecInitBitmapHeapScan((BitmapHeapScan *) node, estate);
+			result = (PlanState *) ExecInitBitmapHeapScan((BitmapHeapScan *) node,
+														  estate, eflags);
 			break;
 
 		case T_TidScan:
-			result = (PlanState *) ExecInitTidScan((TidScan *) node, estate);
+			result = (PlanState *) ExecInitTidScan((TidScan *) node,
+												   estate, eflags);
 			break;
 
 		case T_SubqueryScan:
-			result = (PlanState *) ExecInitSubqueryScan((SubqueryScan *) node, estate);
+			result = (PlanState *) ExecInitSubqueryScan((SubqueryScan *) node,
+														estate, eflags);
 			break;
 
 		case T_FunctionScan:
-			result = (PlanState *) ExecInitFunctionScan((FunctionScan *) node, estate);
+			result = (PlanState *) ExecInitFunctionScan((FunctionScan *) node,
+														estate, eflags);
 			break;
 
 			/*
 			 * join nodes
 			 */
 		case T_NestLoop:
-			result = (PlanState *) ExecInitNestLoop((NestLoop *) node, estate);
+			result = (PlanState *) ExecInitNestLoop((NestLoop *) node,
+													estate, eflags);
 			break;
 
 		case T_MergeJoin:
-			result = (PlanState *) ExecInitMergeJoin((MergeJoin *) node, estate);
+			result = (PlanState *) ExecInitMergeJoin((MergeJoin *) node,
+													 estate, eflags);
 			break;
 
 		case T_HashJoin:
-			result = (PlanState *) ExecInitHashJoin((HashJoin *) node, estate);
+			result = (PlanState *) ExecInitHashJoin((HashJoin *) node,
+													estate, eflags);
 			break;
 
 			/*
 			 * materialization nodes
 			 */
 		case T_Material:
-			result = (PlanState *) ExecInitMaterial((Material *) node, estate);
+			result = (PlanState *) ExecInitMaterial((Material *) node,
+													estate, eflags);
 			break;
 
 		case T_Sort:
-			result = (PlanState *) ExecInitSort((Sort *) node, estate);
+			result = (PlanState *) ExecInitSort((Sort *) node,
+												estate, eflags);
 			break;
 
 		case T_Group:
-			result = (PlanState *) ExecInitGroup((Group *) node, estate);
+			result = (PlanState *) ExecInitGroup((Group *) node,
+												 estate, eflags);
 			break;
 
 		case T_Agg:
-			result = (PlanState *) ExecInitAgg((Agg *) node, estate);
+			result = (PlanState *) ExecInitAgg((Agg *) node,
+											   estate, eflags);
 			break;
 
 		case T_Unique:
-			result = (PlanState *) ExecInitUnique((Unique *) node, estate);
+			result = (PlanState *) ExecInitUnique((Unique *) node,
+												  estate, eflags);
 			break;
 
 		case T_Hash:
-			result = (PlanState *) ExecInitHash((Hash *) node, estate);
+			result = (PlanState *) ExecInitHash((Hash *) node,
+												estate, eflags);
 			break;
 
 		case T_SetOp:
-			result = (PlanState *) ExecInitSetOp((SetOp *) node, estate);
+			result = (PlanState *) ExecInitSetOp((SetOp *) node,
+												 estate, eflags);
 			break;
 
 		case T_Limit:
-			result = (PlanState *) ExecInitLimit((Limit *) node, estate);
+			result = (PlanState *) ExecInitLimit((Limit *) node,
+												 estate, eflags);
 			break;
 
 		default:
@@ -251,7 +274,7 @@ ExecInitNode(Plan *node, EState *estate)
 
 		Assert(IsA(subplan, SubPlan));
 		sstate = ExecInitExprInitPlan(subplan, result);
-		ExecInitSubPlan(sstate, estate);
+		ExecInitSubPlan(sstate, estate, eflags);
 		subps = lappend(subps, sstate);
 	}
 	result->initPlan = subps;
@@ -267,7 +290,7 @@ ExecInitNode(Plan *node, EState *estate)
 		SubPlanState *sstate = (SubPlanState *) lfirst(l);
 
 		Assert(IsA(sstate, SubPlanState));
-		ExecInitSubPlan(sstate, estate);
+		ExecInitSubPlan(sstate, estate, eflags);
 	}
 
 	/* Set up instrumentation for this node if requested */