Repair problems with EvalPlanQual where target table is scanned as

inner indexscan (ie, one with runtime keys).  ExecIndexReScan must
compute or recompute runtime keys even if we are rescanning in the
EPQ case.  TidScan seems to have comparable problems.  Per bug
noted by Barry Lind 11-Feb-02.

Author: tglsfdc

src/backend/executor/nodeIndexscan.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.65 2001/11/12 17:18:06 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.66 2002/02/11 20:10:48 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -301,24 +301,13 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 	IndexScanState *indexstate;
 	ExprContext *econtext;
 	ScanDirection direction;
+	int			numIndices;
 	IndexScanDescPtr scanDescs;
 	ScanKey    *scanKeys;
-	IndexScanDesc scan;
-	ScanKey		skey;
-	int			numIndices;
-	int			i;
 	int		  **runtimeKeyInfo;
 	int		   *numScanKeys;
-	List	   *indxqual;
-	List	   *qual;
-	int			n_keys;
-	ScanKey		scan_keys;
-	int		   *run_keys;
+	int			i;
 	int			j;
-	Expr	   *clause;
-	Node	   *scanexpr;
-	Datum		scanvalue;
-	bool		isNull;
 
 	estate = node->scan.plan.state;
 	indexstate = node->indxstate;
@@ -330,10 +319,6 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 	scanKeys = indexstate->iss_ScanKeys;
 	runtimeKeyInfo = indexstate->iss_RuntimeKeyInfo;
 	numScanKeys = indexstate->iss_NumScanKeys;
-	if (ScanDirectionIsBackward(node->indxorderdir))
-		indexstate->iss_IndexPtr = numIndices;
-	else
-		indexstate->iss_IndexPtr = -1;
 
 	if (econtext)
 	{
@@ -359,28 +344,27 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 		ResetExprContext(econtext);
 	}
 
-	/* If this is re-scanning of PlanQual ... */
-	if (estate->es_evTuple != NULL &&
-		estate->es_evTuple[node->scan.scanrelid - 1] != NULL)
-	{
-		estate->es_evTupleNull[node->scan.scanrelid - 1] = false;
-		return;
-	}
-
 	/*
-	 * get the index qualifications and recalculate the appropriate values
+	 * If we are doing runtime key calculations (ie, the index keys depend
+	 * on data from an outer scan), compute the new key values
 	 */
-	indxqual = node->indxqual;
-	for (i = 0; i < numIndices; i++)
+	if (runtimeKeyInfo)
 	{
-		qual = lfirst(indxqual);
-		indxqual = lnext(indxqual);
-		n_keys = numScanKeys[i];
-		scan_keys = (ScanKey) scanKeys[i];
+		List	   *indxqual;
 
-		if (runtimeKeyInfo)
+		indxqual = node->indxqual;
+		for (i = 0; i < numIndices; i++)
 		{
+			List	   *qual = lfirst(indxqual);
+			int			n_keys;
+			ScanKey		scan_keys;
+			int		   *run_keys;
+
+			indxqual = lnext(indxqual);
+			n_keys = numScanKeys[i];
+			scan_keys = scanKeys[i];
 			run_keys = runtimeKeyInfo[i];
+
 			for (j = 0; j < n_keys; j++)
 			{
 				/*
@@ -398,7 +382,11 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 				 */
 				if (run_keys[j] != NO_OP)
 				{
-					clause = nth(j, qual);
+					Expr	   *clause = nth(j, qual);
+					Node	   *scanexpr;
+					Datum		scanvalue;
+					bool		isNull;
+
 					scanexpr = (run_keys[j] == RIGHT_OP) ?
 						(Node *) get_rightop(clause) :
 						(Node *) get_leftop(clause);
@@ -415,13 +403,31 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 				}
 			}
 		}
-		scan = scanDescs[i];
-		skey = scanKeys[i];
-		index_rescan(scan, direction, skey);
-	}
 
-	if (runtimeKeyInfo)
 		indexstate->iss_RuntimeKeysReady = true;
+	}
+
+	/* If this is re-scanning of PlanQual ... */
+	if (estate->es_evTuple != NULL &&
+		estate->es_evTuple[node->scan.scanrelid - 1] != NULL)
+	{
+		estate->es_evTupleNull[node->scan.scanrelid - 1] = false;
+		return;
+	}
+
+	/* reset index scans */
+	if (ScanDirectionIsBackward(node->indxorderdir))
+		indexstate->iss_IndexPtr = numIndices;
+	else
+		indexstate->iss_IndexPtr = -1;
+
+	for (i = 0; i < numIndices; i++)
+	{
+		IndexScanDesc scan = scanDescs[i];
+		ScanKey		skey = scanKeys[i];
+
+		index_rescan(scan, direction, skey);
+	}
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeTidscan.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeTidscan.c,v 1.21 2001/10/28 06:25:43 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeTidscan.c,v 1.22 2002/02/11 20:10:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -108,6 +108,11 @@ TidNext(TidScan *node)
 		if (estate->es_evTupleNull[node->scan.scanrelid - 1])
 			return slot;		/* return empty slot */
 
+		/*
+		 * XXX shouldn't we check here to make sure tuple matches TID list?
+		 * In runtime-key case this is not certain, is it?
+		 */
+
 		ExecStoreTuple(estate->es_evTuple[node->scan.scanrelid - 1],
 					   slot, InvalidBuffer, false);
 
@@ -250,16 +255,22 @@ ExecTidReScan(TidScan *node, ExprContext *exprCtxt, Plan *parent)
 	TidScanState *tidstate;
 	ItemPointerData *tidList;
 
-	tidstate = node->tidstate;
 	estate = node->scan.plan.state;
-	tidstate->tss_TidPtr = -1;
+	tidstate = node->tidstate;
 	tidList = tidstate->tss_TidList;
 
 	/* If we are being passed an outer tuple, save it for runtime key calc */
 	if (exprCtxt != NULL)
 		node->scan.scanstate->cstate.cs_ExprContext->ecxt_outertuple =
 			exprCtxt->ecxt_outertuple;
 
+	/* do runtime calc of target TIDs, if needed */
+	if (node->needRescan)
+		tidstate->tss_NumTids =
+			TidListCreate(node->tideval,
+						  node->scan.scanstate->cstate.cs_ExprContext,
+						  tidList);
+
 	/* If this is re-scanning of PlanQual ... */
 	if (estate->es_evTuple != NULL &&
 		estate->es_evTuple[node->scan.scanrelid - 1] != NULL)
@@ -268,9 +279,7 @@ ExecTidReScan(TidScan *node, ExprContext *exprCtxt, Plan *parent)
 		return;
 	}
 
-	tidstate->tss_NumTids = TidListCreate(node->tideval,
-							 node->scan.scanstate->cstate.cs_ExprContext,
-										  tidList);
+	tidstate->tss_TidPtr = -1;
 
 	/*
 	 * perhaps return something meaningful
@@ -432,7 +441,9 @@ ExecInitTidScan(TidScan *node, EState *estate, Plan *parent)
 	tidList = (ItemPointerData *) palloc(length(node->tideval) * sizeof(ItemPointerData));
 	numTids = 0;
 	if (!node->needRescan)
-		numTids = TidListCreate(node->tideval, scanstate->cstate.cs_ExprContext, tidList);
+		numTids = TidListCreate(node->tideval,
+								scanstate->cstate.cs_ExprContext,
+								tidList);
 	tidPtr = -1;
 
 	CXT1_printf("ExecInitTidScan: context is %d\n", CurrentMemoryContext);