diff options
Diffstat (limited to 'src/backend/tcop/pquery.c')
| -rw-r--r-- | src/backend/tcop/pquery.c | 164 |
1 files changed, 97 insertions, 67 deletions
diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c index 280f269c8f..0cb7865a9f 100644 --- a/src/backend/tcop/pquery.c +++ b/src/backend/tcop/pquery.c @@ -8,13 +8,14 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/tcop/pquery.c,v 1.61 2003/05/06 00:20:33 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/tcop/pquery.c,v 1.62 2003/05/06 20:26:27 tgl Exp $ * *------------------------------------------------------------------------- */ #include "postgres.h" #include "executor/executor.h" +#include "executor/tstoreReceiver.h" #include "miscadmin.h" #include "tcop/tcopprot.h" #include "tcop/pquery.h" @@ -24,18 +25,18 @@ static uint32 RunFromStore(Portal portal, ScanDirection direction, long count, - CommandDest dest); + DestReceiver *dest); static long PortalRunSelect(Portal portal, bool forward, long count, - CommandDest dest); + DestReceiver *dest); static void PortalRunUtility(Portal portal, Query *query, - CommandDest dest, char *completionTag); + DestReceiver *dest, char *completionTag); static void PortalRunMulti(Portal portal, - CommandDest dest, CommandDest altdest, + DestReceiver *dest, DestReceiver *altdest, char *completionTag); static long DoPortalRunFetch(Portal portal, FetchDirection fdirection, long count, - CommandDest dest); + DestReceiver *dest); static void DoPortalRewind(Portal portal); @@ -45,7 +46,7 @@ static void DoPortalRewind(Portal portal); QueryDesc * CreateQueryDesc(Query *parsetree, Plan *plantree, - CommandDest dest, + DestReceiver *dest, const char *portalName, ParamListInfo params, bool doInstrument) @@ -103,7 +104,7 @@ ProcessQuery(Query *parsetree, Plan *plan, ParamListInfo params, const char *portalName, - CommandDest dest, + DestReceiver *dest, char *completionTag) { int operation = parsetree->commandType; @@ -123,7 +124,7 @@ ProcessQuery(Query *parsetree, * special-cases this case. (Perhaps would be cleaner to have * an additional destination type?) */ - dest = None; + dest = None_Receiver; } } @@ -185,6 +186,39 @@ ProcessQuery(Query *parsetree, FreeQueryDesc(queryDesc); } +/* + * ChoosePortalStrategy + * Select portal execution strategy given the intended query list. + * + * See the comments in portal.h. + */ +PortalStrategy +ChoosePortalStrategy(List *parseTrees) +{ + PortalStrategy strategy; + + strategy = PORTAL_MULTI_QUERY; /* default assumption */ + + if (length(parseTrees) == 1) + { + Query *query = (Query *) lfirst(parseTrees); + + if (query->commandType == CMD_SELECT && + query->canSetTag && + query->into == NULL) + { + strategy = PORTAL_ONE_SELECT; + } + else if (query->commandType == CMD_UTILITY && + query->canSetTag && + query->utilityStmt != NULL) + { + if (UtilityReturnsTuples(query->utilityStmt)) + strategy = PORTAL_UTIL_SELECT; + } + } + return strategy; +} /* * PortalStart @@ -202,7 +236,6 @@ void PortalStart(Portal portal, ParamListInfo params) { MemoryContext oldContext; - Query *query = NULL; QueryDesc *queryDesc; AssertArg(PortalIsValid(portal)); @@ -215,23 +248,9 @@ PortalStart(Portal portal, ParamListInfo params) portal->portalParams = params; /* - * Determine the portal execution strategy (see comments in portal.h) + * Determine the portal execution strategy */ - portal->strategy = PORTAL_MULTI_QUERY; /* default assumption */ - if (length(portal->parseTrees) == 1) - { - query = (Query *) lfirst(portal->parseTrees); - if (query->commandType == CMD_SELECT && - query->canSetTag && - query->into == NULL) - portal->strategy = PORTAL_ONE_SELECT; - else if (query->commandType == CMD_UTILITY && - query->canSetTag && - query->utilityStmt != NULL) - { - /* XXX check for things that can be PORTAL_UTIL_SELECT */ - } - } + portal->strategy = ChoosePortalStrategy(portal->parseTrees); /* * Fire her up according to the strategy @@ -247,9 +266,9 @@ PortalStart(Portal portal, ParamListInfo params) * Create QueryDesc in portal's context; for the moment, set * the destination to None. */ - queryDesc = CreateQueryDesc(query, + queryDesc = CreateQueryDesc((Query *) lfirst(portal->parseTrees), (Plan *) lfirst(portal->planTrees), - None, + None_Receiver, portal->name, params, false); @@ -261,6 +280,9 @@ PortalStart(Portal portal, ParamListInfo params) * This tells PortalCleanup to shut down the executor */ portal->queryDesc = queryDesc; + /* + * Remember tuple descriptor + */ portal->tupDesc = queryDesc->tupDesc; /* * Reset cursor position data to "start of query" @@ -272,10 +294,19 @@ PortalStart(Portal portal, ParamListInfo params) break; case PORTAL_UTIL_SELECT: - /* XXX implement later */ - /* XXX query snapshot here? no, RunUtility will do it */ - /* xxx what about Params? */ - portal->tupDesc = NULL; + /* + * We don't set query snapshot here, because PortalRunUtility + * will take care of it. + */ + portal->tupDesc = + UtilityTupleDescriptor(((Query *) lfirst(portal->parseTrees))->utilityStmt); + /* + * Reset cursor position data to "start of query" + */ + portal->atStart = true; + portal->atEnd = false; /* allow fetches */ + portal->portalPos = 0; + portal->posOverflow = false; break; case PORTAL_MULTI_QUERY: @@ -310,11 +341,11 @@ PortalStart(Portal portal, ParamListInfo params) * suspended due to exhaustion of the count parameter. */ bool -PortalRun(Portal portal, long count, CommandDest dest, CommandDest altdest, +PortalRun(Portal portal, long count, + DestReceiver *dest, DestReceiver *altdest, char *completionTag) { bool result; - Portal saveCurrentPortal; MemoryContext savePortalContext; MemoryContext saveQueryContext; MemoryContext oldContext; @@ -336,10 +367,8 @@ PortalRun(Portal portal, long count, CommandDest dest, CommandDest altdest, portal->portalActive = true; /* - * Set global portal and context pointers. + * Set global portal context pointers. */ - saveCurrentPortal = CurrentPortal; - CurrentPortal = portal; savePortalContext = PortalContext; PortalContext = PortalGetHeapMemory(portal); saveQueryContext = QueryContext; @@ -367,8 +396,14 @@ PortalRun(Portal portal, long count, CommandDest dest, CommandDest altdest, */ if (!portal->portalUtilReady) { + DestReceiver *treceiver; + + PortalCreateHoldStore(portal); + treceiver = CreateTuplestoreDestReceiver(portal->holdStore, + portal->holdContext); PortalRunUtility(portal, lfirst(portal->parseTrees), - Tuplestore, NULL); + treceiver, NULL); + (*treceiver->destroy) (treceiver); portal->portalUtilReady = true; } /* @@ -404,7 +439,6 @@ PortalRun(Portal portal, long count, CommandDest dest, CommandDest altdest, /* Mark portal not active */ portal->portalActive = false; - CurrentPortal = saveCurrentPortal; PortalContext = savePortalContext; QueryContext = saveQueryContext; @@ -431,7 +465,7 @@ long PortalRunSelect(Portal portal, bool forward, long count, - CommandDest dest) + DestReceiver *dest) { QueryDesc *queryDesc; ScanDirection direction; @@ -568,21 +602,18 @@ PortalRunSelect(Portal portal, */ static uint32 RunFromStore(Portal portal, ScanDirection direction, long count, - CommandDest dest) + DestReceiver *dest) { - DestReceiver *destfunc; List *targetlist; long current_tuple_count = 0; - destfunc = DestToFunction(dest); - if (portal->strategy == PORTAL_ONE_SELECT) targetlist = ((Plan *) lfirst(portal->planTrees))->targetlist; else targetlist = NIL; - (*destfunc->setup) (destfunc, CMD_SELECT, portal->name, portal->tupDesc, - targetlist); + (*dest->startup) (dest, CMD_SELECT, portal->name, portal->tupDesc, + targetlist); if (direction == NoMovementScanDirection) { @@ -608,7 +639,7 @@ RunFromStore(Portal portal, ScanDirection direction, long count, if (tup == NULL) break; - (*destfunc->receiveTuple) (tup, portal->tupDesc, destfunc); + (*dest->receiveTuple) (tup, portal->tupDesc, dest); if (should_free) pfree(tup); @@ -624,7 +655,7 @@ RunFromStore(Portal portal, ScanDirection direction, long count, } } - (*destfunc->cleanup) (destfunc); + (*dest->shutdown) (dest); return (uint32) current_tuple_count; } @@ -635,7 +666,7 @@ RunFromStore(Portal portal, ScanDirection direction, long count, */ static void PortalRunUtility(Portal portal, Query *query, - CommandDest dest, char *completionTag) + DestReceiver *dest, char *completionTag) { Node *utilityStmt = query->utilityStmt; @@ -690,7 +721,7 @@ PortalRunUtility(Portal portal, Query *query, */ static void PortalRunMulti(Portal portal, - CommandDest dest, CommandDest altdest, + DestReceiver *dest, DestReceiver *altdest, char *completionTag) { List *plantree_list = portal->planTrees; @@ -807,10 +838,9 @@ long PortalRunFetch(Portal portal, FetchDirection fdirection, long count, - CommandDest dest) + DestReceiver *dest) { long result; - Portal saveCurrentPortal; MemoryContext savePortalContext; MemoryContext saveQueryContext; MemoryContext oldContext; @@ -828,10 +858,8 @@ PortalRunFetch(Portal portal, portal->portalActive = true; /* - * Set global portal and context pointers. + * Set global portal context pointers. */ - saveCurrentPortal = CurrentPortal; - CurrentPortal = portal; savePortalContext = PortalContext; PortalContext = PortalGetHeapMemory(portal); saveQueryContext = QueryContext; @@ -856,7 +884,6 @@ PortalRunFetch(Portal portal, /* Mark portal not active */ portal->portalActive = false; - CurrentPortal = saveCurrentPortal; PortalContext = savePortalContext; QueryContext = saveQueryContext; @@ -873,7 +900,7 @@ static long DoPortalRunFetch(Portal portal, FetchDirection fdirection, long count, - CommandDest dest) + DestReceiver *dest) { bool forward; @@ -912,7 +939,8 @@ DoPortalRunFetch(Portal portal, { DoPortalRewind(portal); if (count > 1) - PortalRunSelect(portal, true, count-1, None); + PortalRunSelect(portal, true, count-1, + None_Receiver); } else { @@ -921,9 +949,11 @@ DoPortalRunFetch(Portal portal, if (portal->atEnd) pos++; /* need one extra fetch if off end */ if (count <= pos) - PortalRunSelect(portal, false, pos-count+1, None); + PortalRunSelect(portal, false, pos-count+1, + None_Receiver); else if (count > pos+1) - PortalRunSelect(portal, true, count-pos-1, None); + PortalRunSelect(portal, true, count-pos-1, + None_Receiver); } return PortalRunSelect(portal, true, 1L, dest); } @@ -936,9 +966,9 @@ DoPortalRunFetch(Portal portal, * (Is it worth considering case where count > half of size * of query? We could rewind once we know the size ...) */ - PortalRunSelect(portal, true, FETCH_ALL, None); + PortalRunSelect(portal, true, FETCH_ALL, None_Receiver); if (count < -1) - PortalRunSelect(portal, false, -count-1, None); + PortalRunSelect(portal, false, -count-1, None_Receiver); return PortalRunSelect(portal, false, 1L, dest); } else /* count == 0 */ @@ -955,7 +985,7 @@ DoPortalRunFetch(Portal portal, * Definition: advance count-1 rows, return next row (if any). */ if (count > 1) - PortalRunSelect(portal, true, count-1, None); + PortalRunSelect(portal, true, count-1, None_Receiver); return PortalRunSelect(portal, true, 1L, dest); } else if (count < 0) @@ -965,7 +995,7 @@ DoPortalRunFetch(Portal portal, * (if any). */ if (count < -1) - PortalRunSelect(portal, false, -count-1, None); + PortalRunSelect(portal, false, -count-1, None_Receiver); return PortalRunSelect(portal, false, 1L, dest); } else /* count == 0 */ @@ -995,7 +1025,7 @@ DoPortalRunFetch(Portal portal, /* Are we sitting on a row? */ on_row = (!portal->atStart && !portal->atEnd); - if (dest == None) + if (dest->mydest == None) { /* MOVE 0 returns 0/1 based on if FETCH 0 would return a row */ return on_row ? 1L : 0L; @@ -1011,7 +1041,7 @@ DoPortalRunFetch(Portal portal, */ if (on_row) { - PortalRunSelect(portal, false, 1L, None); + PortalRunSelect(portal, false, 1L, None_Receiver); /* Set up to fetch one row forward */ count = 1; forward = true; @@ -1022,7 +1052,7 @@ DoPortalRunFetch(Portal portal, /* * Optimize MOVE BACKWARD ALL into a Rewind. */ - if (!forward && count == FETCH_ALL && dest == None) + if (!forward && count == FETCH_ALL && dest->mydest == None) { long result = portal->portalPos; |