From 0a1e28494e1a55a2a700bbfce0d839019a6d3fb5 Mon Sep 17 00:00:00 2001
From: "Vadim B. Mikheev" <vadim4o@yahoo.com>
Date: Fri, 27 Feb 1998 16:11:28 +0000
Subject: [PATCH] ExecReScan for MergeJoin.
Marked inner tuple now is copied into mergestate->mj_MarkedTupleSlot -
no more tricks arround ttc_shouldfree.
---
src/backend/executor/execAmi.c | 7 +-
src/backend/executor/nodeMergejoin.c | 156 ++++++++++++---------------
2 files changed, 75 insertions(+), 88 deletions(-)
diff --git a/src/backend/executor/execAmi.c b/src/backend/executor/execAmi.c
index b2851d83b4a..0497c922ef1 100644
--- a/src/backend/executor/execAmi.c
+++ b/src/backend/executor/execAmi.c
@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/executor/execAmi.c,v 1.19 1998/02/26 04:31:08 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/executor/execAmi.c,v 1.20 1998/02/27 16:11:26 vadim Exp $
*
*-------------------------------------------------------------------------
*/
@@ -44,6 +44,7 @@
#include "executor/nodeAgg.h"
#include "executor/nodeResult.h"
#include "executor/nodeUnique.h"
+#include "executor/nodeMergejoin.h"
#include "executor/nodeSubplan.h"
#include "executor/execdebug.h"
#include "optimizer/internal.h" /* for _TEMP_RELATION_ID_ */
@@ -366,6 +367,10 @@ ExecReScan(Plan *node, ExprContext *exprCtxt, Plan *parent)
ExecReScanSort((Sort *) node, exprCtxt, parent);
break;
+ case T_MergeJoin:
+ ExecReScanMergeJoin((MergeJoin *) node, exprCtxt, parent);
+ break;
+
/*
* Tee is never used
case T_Tee:
diff --git a/src/backend/executor/nodeMergejoin.c b/src/backend/executor/nodeMergejoin.c
index 005047f337f..211160b9e4a 100644
--- a/src/backend/executor/nodeMergejoin.c
+++ b/src/backend/executor/nodeMergejoin.c
@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.13 1998/02/26 04:31:30 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.14 1998/02/27 16:11:28 vadim Exp $
*
*-------------------------------------------------------------------------
*/
@@ -77,6 +77,7 @@
*/
#include "postgres.h"
+#include "access/heapam.h"
#include "executor/executor.h"
#include "executor/execdefs.h"
#include "executor/nodeMergejoin.h"
@@ -86,46 +87,14 @@
static bool MergeCompare(List *eqQual, List *compareQual, ExprContext *econtext);
-/* ----------------------------------------------------------------
- * MarkInnerTuple and RestoreInnerTuple macros
- *
- * when we "mark" a tuple, we place a pointer to it
- * in the marked tuple slot. now there are two pointers
- * to this tuple and we don't want it to be freed until
- * next time we mark a tuple, so we move the policy to
- * the marked tuple slot and set the inner tuple slot policy
- * to false.
- *
- * But, when we restore the inner tuple, the marked tuple
- * retains the policy. Basically once a tuple is marked, it
- * should only be freed when we mark another tuple. -cim 9/27/90
- *
- * Note: now that we store buffers in the tuple table,
- * we have to also increment buffer reference counts
- * correctly whenever we propagate an additional pointer
- * to a buffer item. Later, when ExecStoreTuple() is
- * called again on this slot, the refcnt is decremented
- * when the old tuple is replaced.
- * ----------------------------------------------------------------
- */
#define MarkInnerTuple(innerTupleSlot, mergestate) \
{ \
- bool shouldFree; \
- shouldFree = ExecSetSlotPolicy(innerTupleSlot, false); \
- ExecStoreTuple(innerTupleSlot->val, \
+ ExecStoreTuple(heap_copytuple(innerTupleSlot->val), \
mergestate->mj_MarkedTupleSlot, \
- innerTupleSlot->ttc_buffer, \
- shouldFree); \
- ExecIncrSlotBufferRefcnt(innerTupleSlot); \
+ InvalidBuffer, \
+ true); \
}
-#define RestoreInnerTuple(innerTupleSlot, markedTupleSlot) \
- ExecStoreTuple(markedTupleSlot->val, \
- innerTupleSlot, \
- markedTupleSlot->ttc_buffer, \
- false); \
- ExecIncrSlotBufferRefcnt(innerTupleSlot)
-
/* ----------------------------------------------------------------
* MJFormOSortopI
*
@@ -467,8 +436,6 @@ ExecMergeJoin(MergeJoin *node)
Plan *outerPlan;
TupleTableSlot *outerTupleSlot;
- TupleTableSlot *markedTupleSlot;
-
ExprContext *econtext;
/* ----------------
@@ -528,8 +495,8 @@ ExecMergeJoin(MergeJoin *node)
* means that this is the first time ExecMergeJoin() has
* been called and so we have to initialize the inner,
* outer and marked tuples as well as various stuff in the
- * expression context. ********************************
- *
+ * expression context.
+ * ********************************
*/
case EXEC_MJ_INITIALIZE:
MJ_printf("ExecMergeJoin: EXEC_MJ_INITIALIZE\n");
@@ -560,19 +527,9 @@ ExecMergeJoin(MergeJoin *node)
econtext->ecxt_innertuple = innerTupleSlot;
econtext->ecxt_outertuple = outerTupleSlot;
- /* ----------------
- * set the marked tuple to nil
- * and initialize its tuple descriptor atttributes.
- * -jeff 10 july 1991
- * ----------------
- */
- ExecClearTuple(mergestate->mj_MarkedTupleSlot);
mergestate->mj_MarkedTupleSlot->ttc_tupleDescriptor =
innerTupleSlot->ttc_tupleDescriptor;
-/*
- mergestate->mj_MarkedTupleSlot->ttc_execTupDescriptor =
- innerTupleSlot->ttc_execTupDescriptor;
-*/
+
/* ----------------
* initialize merge join state to skip inner tuples.
* ----------------
@@ -584,15 +541,14 @@ ExecMergeJoin(MergeJoin *node)
* ******************************** EXEC_MJ_JOINMARK means
* we have just found a new outer tuple and a possible
* matching inner tuple. This is the case after the
- * INITIALIZE, SKIPOUTER or SKIPINNER states. ********************************
- *
+ * INITIALIZE, SKIPOUTER or SKIPINNER states.
+ * ********************************
*/
case EXEC_MJ_JOINMARK:
MJ_printf("ExecMergeJoin: EXEC_MJ_JOINMARK\n");
ExecMarkPos(innerPlan);
- innerTupleSlot = econtext->ecxt_innertuple;
- MarkInnerTuple(innerTupleSlot, mergestate);
+ MarkInnerTuple(econtext->ecxt_innertuple, mergestate);
mergestate->mj_JoinState = EXEC_MJ_JOINTEST;
break;
@@ -724,8 +680,8 @@ ExecMergeJoin(MergeJoin *node)
break;
/*
- * ******************************** EXEC_MJ_TESTOUTER If
- * the new outer tuple and the marked tuple satisify the
+ * ******************************** EXEC_MJ_TESTOUTER
+ * If the new outer tuple and the marked tuple satisify the
* merge clause then we know we have duplicates in the
* outer scan so we have to restore the inner scan to the
* marked tuple and proceed to join the new outer tuples
@@ -749,12 +705,7 @@ ExecMergeJoin(MergeJoin *node)
*
* new outer tuple > marked tuple
*
- ****************************
- *
- *
- *
- *
- *
+ * ****************************
*/
case EXEC_MJ_TESTOUTER:
MJ_printf("ExecMergeJoin: EXEC_MJ_TESTOUTER\n");
@@ -765,29 +716,32 @@ ExecMergeJoin(MergeJoin *node)
* ----------------
*/
innerTupleSlot = econtext->ecxt_innertuple;
- markedTupleSlot = mergestate->mj_MarkedTupleSlot;
- econtext->ecxt_innertuple = markedTupleSlot;
+ econtext->ecxt_innertuple = mergestate->mj_MarkedTupleSlot;
qualResult = ExecQual((List *) mergeclauses, econtext);
MJ_DEBUG_QUAL(mergeclauses, qualResult);
if (qualResult)
{
- /* ----------------
+ /*
* the merge clause matched so now we juggle the slots
* back the way they were and proceed to JOINTEST.
- * ----------------
+ *
+ * I can't understand why we have to go to JOINTEST
+ * and compare outer tuple with the same inner one
+ * again -> go to JOINTUPLES... - vadim 02/27/98
*/
- econtext->ecxt_innertuple = innerTupleSlot;
-
- RestoreInnerTuple(innerTupleSlot, markedTupleSlot);
ExecRestrPos(innerPlan);
+#if 0
mergestate->mj_JoinState = EXEC_MJ_JOINTEST;
+#endif
+ mergestate->mj_JoinState = EXEC_MJ_JOINTUPLES;
}
else
{
+ econtext->ecxt_innertuple = innerTupleSlot;
/* ----------------
* if the inner tuple was nil and the new outer
* tuple didn't match the marked outer tuple then
@@ -809,12 +763,7 @@ ExecMergeJoin(MergeJoin *node)
return NULL;
}
- /* ----------------
- * restore the inner tuple and continue on to
- * skip outer tuples.
- * ----------------
- */
- econtext->ecxt_innertuple = innerTupleSlot;
+ /* continue on to skip outer tuples */
mergestate->mj_JoinState = EXEC_MJ_SKIPOUTER;
}
break;
@@ -853,9 +802,8 @@ ExecMergeJoin(MergeJoin *node)
if (qualResult)
{
ExecMarkPos(innerPlan);
- innerTupleSlot = econtext->ecxt_innertuple;
- MarkInnerTuple(innerTupleSlot, mergestate);
+ MarkInnerTuple(econtext->ecxt_innertuple, mergestate);
mergestate->mj_JoinState = EXEC_MJ_JOINTUPLES;
break;
@@ -958,9 +906,8 @@ ExecMergeJoin(MergeJoin *node)
if (qualResult)
{
ExecMarkPos(innerPlan);
- innerTupleSlot = econtext->ecxt_innertuple;
- MarkInnerTuple(innerTupleSlot, mergestate);
+ MarkInnerTuple(econtext->ecxt_innertuple, mergestate);
mergestate->mj_JoinState = EXEC_MJ_JOINTUPLES;
break;
@@ -1074,10 +1021,11 @@ bool
ExecInitMergeJoin(MergeJoin *node, EState *estate, Plan *parent)
{
MergeJoinState *mergestate;
- List *joinclauses;
- RegProcedure rightsortop;
- RegProcedure leftsortop;
- RegProcedure sortop;
+ List *joinclauses;
+ RegProcedure rightsortop;
+ RegProcedure leftsortop;
+ RegProcedure sortop;
+ TupleTableSlot *mjSlot;
List *OSortopI;
List *ISortopO;
@@ -1120,8 +1068,14 @@ ExecInitMergeJoin(MergeJoin *node, EState *estate, Plan *parent)
* ----------------
*/
ExecInitResultTupleSlot(estate, &mergestate->jstate);
- ExecInitMarkedTupleSlot(estate, mergestate);
-
+ mjSlot = (TupleTableSlot *) palloc(sizeof(TupleTableSlot));
+ mjSlot->val = NULL;
+ mjSlot->ttc_shouldFree = true;
+ mjSlot->ttc_tupleDescriptor = NULL;
+ mjSlot->ttc_whichplan = -1;
+ mjSlot->ttc_descIsNew = true;
+ mergestate->mj_MarkedTupleSlot = mjSlot;
+
/* ----------------
* get merge sort operators.
*
@@ -1245,7 +1199,35 @@ ExecEndMergeJoin(MergeJoin *node)
*/
ExecClearTuple(mergestate->jstate.cs_ResultTupleSlot);
ExecClearTuple(mergestate->mj_MarkedTupleSlot);
-
+ pfree (mergestate->mj_MarkedTupleSlot);
+ mergestate->mj_MarkedTupleSlot = NULL;
+
MJ1_printf("ExecEndMergeJoin: %s\n",
"node processing ended");
}
+
+void
+ExecReScanMergeJoin(MergeJoin *node, ExprContext *exprCtxt, Plan *parent)
+{
+ MergeJoinState *mergestate = node->mergestate;
+ TupleTableSlot *mjSlot = mergestate->mj_MarkedTupleSlot;
+
+ ExecClearTuple(mjSlot);
+ mjSlot->val = NULL;
+ mjSlot->ttc_shouldFree = true;
+ mjSlot->ttc_tupleDescriptor = NULL;
+ mjSlot->ttc_whichplan = -1;
+ mjSlot->ttc_descIsNew = true;
+
+ mergestate->mj_JoinState = EXEC_MJ_INITIALIZE;
+
+ /*
+ * if chgParam of subnodes is not null then plans will be re-scanned by
+ * first ExecProcNode.
+ */
+ if (((Plan *) node)->lefttree->chgParam == NULL)
+ ExecReScan(((Plan *) node)->lefttree, exprCtxt, (Plan *) node);
+ if (((Plan *) node)->righttree->chgParam == NULL)
+ ExecReScan(((Plan *) node)->righttree, exprCtxt, (Plan *) node);
+
+}
--
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