91 lines
1.9 KiB
C
91 lines
1.9 KiB
C
/*-------------------------------------------------------------------------
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*
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* tstoreReceiver.c
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* an implementation of DestReceiver that stores the result tuples in
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* a Tuplestore
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*
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*
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* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/executor/tstoreReceiver.c,v 1.17 2006/06/27 02:51:39 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "executor/tstoreReceiver.h"
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typedef struct
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{
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DestReceiver pub;
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Tuplestorestate *tstore;
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MemoryContext cxt;
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} TStoreState;
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/*
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* Prepare to receive tuples from executor.
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*/
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static void
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tstoreStartupReceiver(DestReceiver *self, int operation, TupleDesc typeinfo)
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{
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/* do nothing */
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}
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/*
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* Receive a tuple from the executor and store it in the tuplestore.
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*/
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static void
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tstoreReceiveSlot(TupleTableSlot *slot, DestReceiver *self)
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{
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TStoreState *myState = (TStoreState *) self;
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MemoryContext oldcxt = MemoryContextSwitchTo(myState->cxt);
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tuplestore_puttupleslot(myState->tstore, slot);
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MemoryContextSwitchTo(oldcxt);
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}
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/*
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* Clean up at end of an executor run
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*/
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static void
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tstoreShutdownReceiver(DestReceiver *self)
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{
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/* do nothing */
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}
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/*
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* Destroy receiver when done with it
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*/
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static void
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tstoreDestroyReceiver(DestReceiver *self)
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{
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pfree(self);
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}
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/*
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* Initially create a DestReceiver object.
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*/
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DestReceiver *
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CreateTuplestoreDestReceiver(Tuplestorestate *tStore,
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MemoryContext tContext)
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{
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TStoreState *self = (TStoreState *) palloc(sizeof(TStoreState));
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self->pub.receiveSlot = tstoreReceiveSlot;
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self->pub.rStartup = tstoreStartupReceiver;
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self->pub.rShutdown = tstoreShutdownReceiver;
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self->pub.rDestroy = tstoreDestroyReceiver;
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self->pub.mydest = DestTuplestore;
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self->tstore = tStore;
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self->cxt = tContext;
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return (DestReceiver *) self;
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}
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