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-rw-r--r--src/backend/executor/execMain.c144
-rw-r--r--src/backend/executor/functions.c7
-rw-r--r--src/backend/executor/spi.c39
3 files changed, 173 insertions, 17 deletions
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 5ce90902b4c..e11869ce783 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -26,7 +26,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.75 1999/02/07 16:17:11 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.76 1999/02/08 14:14:09 wieck Exp $
*
*-------------------------------------------------------------------------
*/
@@ -60,21 +60,27 @@ void ExecCheckPerms(CmdType operation, int resultRelation, List *rangeTable,
/* decls for local routines only used within this module */
-static TupleDesc InitPlan(CmdType operation, Query *parseTree,
- Plan *plan, EState *estate);
-static void EndPlan(Plan *plan, EState *estate);
+static TupleDesc InitPlan(CmdType operation,
+ Query *parseTree,
+ Plan *plan,
+ EState *estate);
+static void EndPlan(Plan *plan,
+ EState *estate);
static TupleTableSlot *ExecutePlan(EState *estate, Plan *plan,
- CmdType operation, int numberTuples, ScanDirection direction,
- DestReceiver *destfunc);
+ CmdType operation,
+ int offsetTuples,
+ int numberTuples,
+ ScanDirection direction,
+ DestReceiver *destfunc);
static void ExecRetrieve(TupleTableSlot *slot,
- DestReceiver *destfunc,
- EState *estate);
+ DestReceiver *destfunc,
+ EState *estate);
static void ExecAppend(TupleTableSlot *slot, ItemPointer tupleid,
- EState *estate);
+ EState *estate);
static void ExecDelete(TupleTableSlot *slot, ItemPointer tupleid,
- EState *estate);
+ EState *estate);
static void ExecReplace(TupleTableSlot *slot, ItemPointer tupleid,
- EState *estate);
+ EState *estate);
TupleTableSlot *EvalPlanQual(EState *estate, Index rti, ItemPointer tid);
static TupleTableSlot *EvalPlanQualNext(EState *estate);
@@ -187,13 +193,16 @@ ExecutorStart(QueryDesc *queryDesc, EState *estate)
* ----------------------------------------------------------------
*/
TupleTableSlot *
-ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
+ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature,
+ Node *limoffset, Node *limcount)
{
CmdType operation;
Plan *plan;
TupleTableSlot *result;
CommandDest dest;
DestReceiver *destfunc;
+ int offset = 0;
+ int count = 0;
/******************
* sanity checks
@@ -222,6 +231,96 @@ ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
*/
(*destfunc->setup) (destfunc, (TupleDesc) NULL);
+ /******************
+ * if given get the offset of the LIMIT clause
+ ******************
+ */
+ if (limoffset != NULL)
+ {
+ Const *coffset;
+ Param *poffset;
+ ParamListInfo paramLI;
+ int i;
+
+ switch (nodeTag(limoffset))
+ {
+ case T_Const:
+ coffset = (Const *)limoffset;
+ offset = (int)(coffset->constvalue);
+ break;
+
+ case T_Param:
+ poffset = (Param *)limoffset;
+ paramLI = estate->es_param_list_info;
+
+ if (paramLI == NULL)
+ elog(ERROR, "parameter for limit offset not in executor state");
+ for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
+ {
+ if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == poffset->paramid)
+ break;
+ }
+ if (paramLI[i].kind == PARAM_INVALID)
+ elog(ERROR, "parameter for limit offset not in executor state");
+ if (paramLI[i].isnull)
+ elog(ERROR, "limit offset cannot be NULL value");
+ offset = (int)(paramLI[i].value);
+
+ break;
+
+ default:
+ elog(ERROR, "unexpected node type %d as limit offset", nodeTag(limoffset));
+ }
+
+ if (offset < 0)
+ elog(ERROR, "limit offset cannot be negative");
+ }
+
+ /******************
+ * if given get the count of the LIMIT clause
+ ******************
+ */
+ if (limcount != NULL)
+ {
+ Const *ccount;
+ Param *pcount;
+ ParamListInfo paramLI;
+ int i;
+
+ switch (nodeTag(limcount))
+ {
+ case T_Const:
+ ccount = (Const *)limcount;
+ count = (int)(ccount->constvalue);
+ break;
+
+ case T_Param:
+ pcount = (Param *)limcount;
+ paramLI = estate->es_param_list_info;
+
+ if (paramLI == NULL)
+ elog(ERROR, "parameter for limit count not in executor state");
+ for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
+ {
+ if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == pcount->paramid)
+ break;
+ }
+ if (paramLI[i].kind == PARAM_INVALID)
+ elog(ERROR, "parameter for limit count not in executor state");
+ if (paramLI[i].isnull)
+ elog(ERROR, "limit count cannot be NULL value");
+ count = (int)(paramLI[i].value);
+
+ break;
+
+ default:
+ elog(ERROR, "unexpected node type %d as limit count", nodeTag(limcount));
+ }
+
+ if (count < 0)
+ elog(ERROR, "limit count cannot be negative");
+ }
+
switch (feature)
{
@@ -229,7 +328,8 @@ ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
result = ExecutePlan(estate,
plan,
operation,
- ALL_TUPLES,
+ offset,
+ count,
ForwardScanDirection,
destfunc);
break;
@@ -237,6 +337,7 @@ ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
result = ExecutePlan(estate,
plan,
operation,
+ offset,
count,
ForwardScanDirection,
destfunc);
@@ -250,6 +351,7 @@ ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
result = ExecutePlan(estate,
plan,
operation,
+ offset,
count,
BackwardScanDirection,
destfunc);
@@ -264,6 +366,7 @@ ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
result = ExecutePlan(estate,
plan,
operation,
+ 0,
ONE_TUPLE,
ForwardScanDirection,
destfunc);
@@ -784,6 +887,7 @@ static TupleTableSlot *
ExecutePlan(EState *estate,
Plan *plan,
CmdType operation,
+ int offsetTuples,
int numberTuples,
ScanDirection direction,
DestReceiver* destfunc)
@@ -846,6 +950,20 @@ lnext:;
}
/******************
+ * For now we completely execute the plan and skip
+ * result tuples if requested by LIMIT offset.
+ * Finally we should try to do it in deeper levels
+ * if possible (during index scan)
+ * - Jan
+ ******************
+ */
+ if (offsetTuples > 0)
+ {
+ --offsetTuples;
+ continue;
+ }
+
+ /******************
* if we have a junk filter, then project a new
* tuple with the junk removed.
*
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 51ea6655e9d..7108a1cab52 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/executor/functions.c,v 1.22 1999/02/03 21:16:12 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/executor/functions.c,v 1.23 1999/02/08 14:14:09 wieck Exp $
*
*-------------------------------------------------------------------------
*/
@@ -130,6 +130,9 @@ init_execution_state(FunctionCachePtr fcache,
None);
estate = CreateExecutorState();
+ if (queryTree->limitOffset != NULL || queryTree->limitCount != NULL)
+ elog(ERROR, "LIMIT clause from SQL functions not yet implemented");
+
if (nargs > 0)
{
int i;
@@ -199,7 +202,7 @@ postquel_getnext(execution_state *es)
feature = (LAST_POSTQUEL_COMMAND(es)) ? EXEC_RETONE : EXEC_RUN;
- return ExecutorRun(es->qd, es->estate, feature, 0);
+ return ExecutorRun(es->qd, es->estate, feature, (Node *)NULL, (Node *)NULL);
}
static void
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 7ca2a6c21e5..397f68a4055 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -3,7 +3,7 @@
* spi.c--
* Server Programming Interface
*
- * $Id: spi.c,v 1.32 1999/01/27 16:15:20 wieck Exp $
+ * $Id: spi.c,v 1.33 1999/02/08 14:14:10 wieck Exp $
*
*-------------------------------------------------------------------------
*/
@@ -779,6 +779,8 @@ _SPI_pquery(QueryDesc *queryDesc, EState *state, int tcount)
bool isRetrieveIntoRelation = false;
char *intoName = NULL;
int res;
+ Const tcount_const;
+ Node *count = NULL;
switch (operation)
{
@@ -813,6 +815,39 @@ _SPI_pquery(QueryDesc *queryDesc, EState *state, int tcount)
return SPI_ERROR_OPUNKNOWN;
}
+ /* ----------------
+ * Get the query LIMIT tuple count
+ * ----------------
+ */
+ if (parseTree->limitCount != NULL)
+ {
+ /* ----------------
+ * A limit clause in the parsetree overrides the
+ * tcount parameter
+ * ----------------
+ */
+ count = parseTree->limitCount;
+ }
+ else
+ {
+ /* ----------------
+ * No LIMIT clause in parsetree. Use a local Const node
+ * to put tcount into it
+ * ----------------
+ */
+ memset(&tcount_const, 0, sizeof(tcount_const));
+ tcount_const.type = T_Const;
+ tcount_const.consttype = INT4OID;
+ tcount_const.constlen = sizeof(int4);
+ tcount_const.constvalue = (Datum)tcount;
+ tcount_const.constisnull = FALSE;
+ tcount_const.constbyval = TRUE;
+ tcount_const.constisset = FALSE;
+ tcount_const.constiscast = FALSE;
+
+ count = (Node *)&tcount_const;
+ }
+
if (state == NULL) /* plan preparation */
return res;
#ifdef SPI_EXECUTOR_STATS
@@ -833,7 +868,7 @@ _SPI_pquery(QueryDesc *queryDesc, EState *state, int tcount)
return SPI_OK_CURSOR;
}
- ExecutorRun(queryDesc, state, EXEC_FOR, tcount);
+ ExecutorRun(queryDesc, state, EXEC_FOR, parseTree->limitOffset, count);
_SPI_current->processed = state->es_processed;
if (operation == CMD_SELECT && queryDesc->dest == SPI)
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-28 09:41:12 +0000