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1021 lines
27 KiB
C
1021 lines
27 KiB
C
/*-------------------------------------------------------------------------
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*
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* execUtils.c
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* miscellaneous executor utility routines
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*
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* Portions Copyright (c) 1996-2017, 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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*
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* IDENTIFICATION
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* src/backend/executor/execUtils.c
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*
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*-------------------------------------------------------------------------
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*/
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/*
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* INTERFACE ROUTINES
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* CreateExecutorState Create/delete executor working state
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* FreeExecutorState
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* CreateExprContext
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* CreateStandaloneExprContext
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* FreeExprContext
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* ReScanExprContext
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*
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* ExecAssignExprContext Common code for plan node init routines.
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* ExecAssignResultType
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* etc
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*
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* ExecOpenScanRelation Common code for scan node init routines.
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* ExecCloseScanRelation
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*
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* executor_errposition Report syntactic position of an error.
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*
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* RegisterExprContextCallback Register function shutdown callback
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* UnregisterExprContextCallback Deregister function shutdown callback
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*
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* GetAttributeByName Runtime extraction of columns from tuples.
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* GetAttributeByNum
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*
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* NOTES
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* This file has traditionally been the place to stick misc.
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* executor support stuff that doesn't really go anyplace else.
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*/
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#include "postgres.h"
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#include "access/relscan.h"
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#include "access/transam.h"
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#include "executor/executor.h"
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#include "mb/pg_wchar.h"
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#include "nodes/nodeFuncs.h"
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#include "parser/parsetree.h"
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#include "storage/lmgr.h"
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#include "utils/builtins.h"
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#include "utils/memutils.h"
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#include "utils/rel.h"
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#include "utils/typcache.h"
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static void ShutdownExprContext(ExprContext *econtext, bool isCommit);
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/* ----------------------------------------------------------------
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* Executor state and memory management functions
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* ----------------------------------------------------------------
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*/
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/* ----------------
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* CreateExecutorState
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*
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* Create and initialize an EState node, which is the root of
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* working storage for an entire Executor invocation.
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*
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* Principally, this creates the per-query memory context that will be
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* used to hold all working data that lives till the end of the query.
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* Note that the per-query context will become a child of the caller's
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* CurrentMemoryContext.
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* ----------------
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*/
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EState *
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CreateExecutorState(void)
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{
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EState *estate;
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MemoryContext qcontext;
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MemoryContext oldcontext;
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/*
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* Create the per-query context for this Executor run.
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*/
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qcontext = AllocSetContextCreate(CurrentMemoryContext,
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"ExecutorState",
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ALLOCSET_DEFAULT_SIZES);
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/*
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* Make the EState node within the per-query context. This way, we don't
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* need a separate pfree() operation for it at shutdown.
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*/
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oldcontext = MemoryContextSwitchTo(qcontext);
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estate = makeNode(EState);
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/*
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* Initialize all fields of the Executor State structure
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*/
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estate->es_direction = ForwardScanDirection;
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estate->es_snapshot = InvalidSnapshot; /* caller must initialize this */
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estate->es_crosscheck_snapshot = InvalidSnapshot; /* no crosscheck */
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estate->es_range_table = NIL;
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estate->es_plannedstmt = NULL;
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estate->es_junkFilter = NULL;
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estate->es_output_cid = (CommandId) 0;
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estate->es_result_relations = NULL;
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estate->es_num_result_relations = 0;
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estate->es_result_relation_info = NULL;
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estate->es_trig_target_relations = NIL;
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estate->es_trig_tuple_slot = NULL;
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estate->es_trig_oldtup_slot = NULL;
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estate->es_trig_newtup_slot = NULL;
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estate->es_param_list_info = NULL;
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estate->es_param_exec_vals = NULL;
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estate->es_queryEnv = NULL;
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estate->es_query_cxt = qcontext;
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estate->es_tupleTable = NIL;
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estate->es_rowMarks = NIL;
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estate->es_processed = 0;
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estate->es_lastoid = InvalidOid;
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estate->es_top_eflags = 0;
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estate->es_instrument = 0;
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estate->es_finished = false;
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estate->es_exprcontexts = NIL;
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estate->es_subplanstates = NIL;
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estate->es_auxmodifytables = NIL;
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estate->es_per_tuple_exprcontext = NULL;
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estate->es_epqTuple = NULL;
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estate->es_epqTupleSet = NULL;
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estate->es_epqScanDone = NULL;
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estate->es_sourceText = NULL;
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/*
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* Return the executor state structure
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*/
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MemoryContextSwitchTo(oldcontext);
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return estate;
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}
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/* ----------------
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* FreeExecutorState
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*
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* Release an EState along with all remaining working storage.
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*
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* Note: this is not responsible for releasing non-memory resources,
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* such as open relations or buffer pins. But it will shut down any
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* still-active ExprContexts within the EState. That is sufficient
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* cleanup for situations where the EState has only been used for expression
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* evaluation, and not to run a complete Plan.
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*
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* This can be called in any memory context ... so long as it's not one
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* of the ones to be freed.
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* ----------------
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*/
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void
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FreeExecutorState(EState *estate)
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{
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/*
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* Shut down and free any remaining ExprContexts. We do this explicitly
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* to ensure that any remaining shutdown callbacks get called (since they
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* might need to release resources that aren't simply memory within the
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* per-query memory context).
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*/
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while (estate->es_exprcontexts)
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{
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/*
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* XXX: seems there ought to be a faster way to implement this than
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* repeated list_delete(), no?
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*/
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FreeExprContext((ExprContext *) linitial(estate->es_exprcontexts),
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true);
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/* FreeExprContext removed the list link for us */
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}
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/*
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* Free the per-query memory context, thereby releasing all working
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* memory, including the EState node itself.
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*/
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MemoryContextDelete(estate->es_query_cxt);
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}
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/* ----------------
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* CreateExprContext
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*
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* Create a context for expression evaluation within an EState.
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*
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* An executor run may require multiple ExprContexts (we usually make one
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* for each Plan node, and a separate one for per-output-tuple processing
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* such as constraint checking). Each ExprContext has its own "per-tuple"
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* memory context.
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*
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* Note we make no assumption about the caller's memory context.
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* ----------------
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*/
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ExprContext *
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CreateExprContext(EState *estate)
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{
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ExprContext *econtext;
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MemoryContext oldcontext;
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/* Create the ExprContext node within the per-query memory context */
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oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
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econtext = makeNode(ExprContext);
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/* Initialize fields of ExprContext */
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econtext->ecxt_scantuple = NULL;
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econtext->ecxt_innertuple = NULL;
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econtext->ecxt_outertuple = NULL;
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econtext->ecxt_per_query_memory = estate->es_query_cxt;
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/*
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* Create working memory for expression evaluation in this context.
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*/
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econtext->ecxt_per_tuple_memory =
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AllocSetContextCreate(estate->es_query_cxt,
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"ExprContext",
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ALLOCSET_DEFAULT_SIZES);
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econtext->ecxt_param_exec_vals = estate->es_param_exec_vals;
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econtext->ecxt_param_list_info = estate->es_param_list_info;
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econtext->ecxt_aggvalues = NULL;
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econtext->ecxt_aggnulls = NULL;
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econtext->caseValue_datum = (Datum) 0;
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econtext->caseValue_isNull = true;
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econtext->domainValue_datum = (Datum) 0;
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econtext->domainValue_isNull = true;
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econtext->ecxt_estate = estate;
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econtext->ecxt_callbacks = NULL;
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/*
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* Link the ExprContext into the EState to ensure it is shut down when the
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* EState is freed. Because we use lcons(), shutdowns will occur in
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* reverse order of creation, which may not be essential but can't hurt.
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*/
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estate->es_exprcontexts = lcons(econtext, estate->es_exprcontexts);
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MemoryContextSwitchTo(oldcontext);
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return econtext;
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}
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/* ----------------
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* CreateStandaloneExprContext
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*
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* Create a context for standalone expression evaluation.
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*
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* An ExprContext made this way can be used for evaluation of expressions
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* that contain no Params, subplans, or Var references (it might work to
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* put tuple references into the scantuple field, but it seems unwise).
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*
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* The ExprContext struct is allocated in the caller's current memory
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* context, which also becomes its "per query" context.
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*
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* It is caller's responsibility to free the ExprContext when done,
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* or at least ensure that any shutdown callbacks have been called
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* (ReScanExprContext() is suitable). Otherwise, non-memory resources
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* might be leaked.
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* ----------------
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*/
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ExprContext *
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CreateStandaloneExprContext(void)
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{
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ExprContext *econtext;
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/* Create the ExprContext node within the caller's memory context */
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econtext = makeNode(ExprContext);
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/* Initialize fields of ExprContext */
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econtext->ecxt_scantuple = NULL;
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econtext->ecxt_innertuple = NULL;
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econtext->ecxt_outertuple = NULL;
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econtext->ecxt_per_query_memory = CurrentMemoryContext;
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/*
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* Create working memory for expression evaluation in this context.
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*/
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econtext->ecxt_per_tuple_memory =
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AllocSetContextCreate(CurrentMemoryContext,
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"ExprContext",
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ALLOCSET_DEFAULT_SIZES);
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econtext->ecxt_param_exec_vals = NULL;
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econtext->ecxt_param_list_info = NULL;
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econtext->ecxt_aggvalues = NULL;
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econtext->ecxt_aggnulls = NULL;
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econtext->caseValue_datum = (Datum) 0;
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econtext->caseValue_isNull = true;
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econtext->domainValue_datum = (Datum) 0;
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econtext->domainValue_isNull = true;
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econtext->ecxt_estate = NULL;
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econtext->ecxt_callbacks = NULL;
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return econtext;
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}
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/* ----------------
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* FreeExprContext
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*
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* Free an expression context, including calling any remaining
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* shutdown callbacks.
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*
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* Since we free the temporary context used for expression evaluation,
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* any previously computed pass-by-reference expression result will go away!
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*
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* If isCommit is false, we are being called in error cleanup, and should
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* not call callbacks but only release memory. (It might be better to call
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* the callbacks and pass the isCommit flag to them, but that would require
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* more invasive code changes than currently seems justified.)
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*
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* Note we make no assumption about the caller's memory context.
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* ----------------
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*/
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void
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FreeExprContext(ExprContext *econtext, bool isCommit)
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{
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EState *estate;
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/* Call any registered callbacks */
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ShutdownExprContext(econtext, isCommit);
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/* And clean up the memory used */
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MemoryContextDelete(econtext->ecxt_per_tuple_memory);
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/* Unlink self from owning EState, if any */
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estate = econtext->ecxt_estate;
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if (estate)
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estate->es_exprcontexts = list_delete_ptr(estate->es_exprcontexts,
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econtext);
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/* And delete the ExprContext node */
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pfree(econtext);
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}
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/*
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* ReScanExprContext
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*
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* Reset an expression context in preparation for a rescan of its
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* plan node. This requires calling any registered shutdown callbacks,
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* since any partially complete set-returning-functions must be canceled.
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*
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* Note we make no assumption about the caller's memory context.
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*/
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void
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ReScanExprContext(ExprContext *econtext)
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{
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/* Call any registered callbacks */
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ShutdownExprContext(econtext, true);
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/* And clean up the memory used */
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MemoryContextReset(econtext->ecxt_per_tuple_memory);
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}
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/*
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* Build a per-output-tuple ExprContext for an EState.
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*
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* This is normally invoked via GetPerTupleExprContext() macro,
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* not directly.
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*/
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ExprContext *
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MakePerTupleExprContext(EState *estate)
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{
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if (estate->es_per_tuple_exprcontext == NULL)
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estate->es_per_tuple_exprcontext = CreateExprContext(estate);
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return estate->es_per_tuple_exprcontext;
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}
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/* ----------------------------------------------------------------
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* miscellaneous node-init support functions
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*
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* Note: all of these are expected to be called with CurrentMemoryContext
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* equal to the per-query memory context.
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* ----------------------------------------------------------------
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*/
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/* ----------------
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* ExecAssignExprContext
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*
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* This initializes the ps_ExprContext field. It is only necessary
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* to do this for nodes which use ExecQual or ExecProject
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* because those routines require an econtext. Other nodes that
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* don't have to evaluate expressions don't need to do this.
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* ----------------
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*/
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void
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ExecAssignExprContext(EState *estate, PlanState *planstate)
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{
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planstate->ps_ExprContext = CreateExprContext(estate);
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}
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/* ----------------
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* ExecAssignResultType
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* ----------------
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*/
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void
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ExecAssignResultType(PlanState *planstate, TupleDesc tupDesc)
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{
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TupleTableSlot *slot = planstate->ps_ResultTupleSlot;
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ExecSetSlotDescriptor(slot, tupDesc);
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}
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/* ----------------
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* ExecAssignResultTypeFromTL
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* ----------------
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*/
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void
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ExecAssignResultTypeFromTL(PlanState *planstate)
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{
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bool hasoid;
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TupleDesc tupDesc;
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if (ExecContextForcesOids(planstate, &hasoid))
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{
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/* context forces OID choice; hasoid is now set correctly */
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}
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else
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{
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/* given free choice, don't leave space for OIDs in result tuples */
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hasoid = false;
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}
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/*
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* ExecTypeFromTL needs the parse-time representation of the tlist, not a
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* list of ExprStates. This is good because some plan nodes don't bother
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* to set up planstate->targetlist ...
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*/
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tupDesc = ExecTypeFromTL(planstate->plan->targetlist, hasoid);
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ExecAssignResultType(planstate, tupDesc);
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}
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/* ----------------
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* ExecGetResultType
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* ----------------
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*/
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TupleDesc
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ExecGetResultType(PlanState *planstate)
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{
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TupleTableSlot *slot = planstate->ps_ResultTupleSlot;
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return slot->tts_tupleDescriptor;
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}
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/* ----------------
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* ExecAssignProjectionInfo
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*
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* forms the projection information from the node's targetlist
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*
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* Notes for inputDesc are same as for ExecBuildProjectionInfo: supply it
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* for a relation-scan node, can pass NULL for upper-level nodes
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* ----------------
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*/
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void
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ExecAssignProjectionInfo(PlanState *planstate,
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TupleDesc inputDesc)
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{
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planstate->ps_ProjInfo =
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ExecBuildProjectionInfo(planstate->plan->targetlist,
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planstate->ps_ExprContext,
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planstate->ps_ResultTupleSlot,
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planstate,
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inputDesc);
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}
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/* ----------------
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* ExecFreeExprContext
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*
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* A plan node's ExprContext should be freed explicitly during executor
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* shutdown because there may be shutdown callbacks to call. (Other resources
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* made by the above routines, such as projection info, don't need to be freed
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* explicitly because they're just memory in the per-query memory context.)
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*
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* However ... there is no particular need to do it during ExecEndNode,
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* because FreeExecutorState will free any remaining ExprContexts within
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* the EState. Letting FreeExecutorState do it allows the ExprContexts to
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* be freed in reverse order of creation, rather than order of creation as
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* will happen if we delete them here, which saves O(N^2) work in the list
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* cleanup inside FreeExprContext.
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* ----------------
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*/
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void
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ExecFreeExprContext(PlanState *planstate)
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{
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/*
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* Per above discussion, don't actually delete the ExprContext. We do
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* unlink it from the plan node, though.
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*/
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planstate->ps_ExprContext = NULL;
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}
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/* ----------------------------------------------------------------
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* the following scan type support functions are for
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* those nodes which are stubborn and return tuples in
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* their Scan tuple slot instead of their Result tuple
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* slot.. luck fur us, these nodes do not do projections
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* so we don't have to worry about getting the ProjectionInfo
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* right for them... -cim 6/3/91
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* ----------------------------------------------------------------
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*/
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/* ----------------
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* ExecAssignScanType
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* ----------------
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*/
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void
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ExecAssignScanType(ScanState *scanstate, TupleDesc tupDesc)
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{
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TupleTableSlot *slot = scanstate->ss_ScanTupleSlot;
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ExecSetSlotDescriptor(slot, tupDesc);
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}
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/* ----------------
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* ExecAssignScanTypeFromOuterPlan
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* ----------------
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*/
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void
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ExecAssignScanTypeFromOuterPlan(ScanState *scanstate)
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{
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PlanState *outerPlan;
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TupleDesc tupDesc;
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outerPlan = outerPlanState(scanstate);
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tupDesc = ExecGetResultType(outerPlan);
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ExecAssignScanType(scanstate, tupDesc);
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}
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/* ----------------------------------------------------------------
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* Scan node support
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* ----------------------------------------------------------------
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*/
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|
|
/* ----------------------------------------------------------------
|
|
* ExecRelationIsTargetRelation
|
|
*
|
|
* Detect whether a relation (identified by rangetable index)
|
|
* is one of the target relations of the query.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
bool
|
|
ExecRelationIsTargetRelation(EState *estate, Index scanrelid)
|
|
{
|
|
ResultRelInfo *resultRelInfos;
|
|
int i;
|
|
|
|
resultRelInfos = estate->es_result_relations;
|
|
for (i = 0; i < estate->es_num_result_relations; i++)
|
|
{
|
|
if (resultRelInfos[i].ri_RangeTableIndex == scanrelid)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecOpenScanRelation
|
|
*
|
|
* Open the heap relation to be scanned by a base-level scan plan node.
|
|
* This should be called during the node's ExecInit routine.
|
|
*
|
|
* By default, this acquires AccessShareLock on the relation. However,
|
|
* if the relation was already locked by InitPlan, we don't need to acquire
|
|
* any additional lock. This saves trips to the shared lock manager.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
Relation
|
|
ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags)
|
|
{
|
|
Relation rel;
|
|
Oid reloid;
|
|
LOCKMODE lockmode;
|
|
|
|
/*
|
|
* Determine the lock type we need. First, scan to see if target relation
|
|
* is a result relation. If not, check if it's a FOR UPDATE/FOR SHARE
|
|
* relation. In either of those cases, we got the lock already.
|
|
*/
|
|
lockmode = AccessShareLock;
|
|
if (ExecRelationIsTargetRelation(estate, scanrelid))
|
|
lockmode = NoLock;
|
|
else
|
|
{
|
|
/* Keep this check in sync with InitPlan! */
|
|
ExecRowMark *erm = ExecFindRowMark(estate, scanrelid, true);
|
|
|
|
if (erm != NULL && erm->relation != NULL)
|
|
lockmode = NoLock;
|
|
}
|
|
|
|
/* Open the relation and acquire lock as needed */
|
|
reloid = getrelid(scanrelid, estate->es_range_table);
|
|
rel = heap_open(reloid, lockmode);
|
|
|
|
/*
|
|
* Complain if we're attempting a scan of an unscannable relation, except
|
|
* when the query won't actually be run. This is a slightly klugy place
|
|
* to do this, perhaps, but there is no better place.
|
|
*/
|
|
if ((eflags & (EXEC_FLAG_EXPLAIN_ONLY | EXEC_FLAG_WITH_NO_DATA)) == 0 &&
|
|
!RelationIsScannable(rel))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("materialized view \"%s\" has not been populated",
|
|
RelationGetRelationName(rel)),
|
|
errhint("Use the REFRESH MATERIALIZED VIEW command.")));
|
|
|
|
return rel;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecCloseScanRelation
|
|
*
|
|
* Close the heap relation scanned by a base-level scan plan node.
|
|
* This should be called during the node's ExecEnd routine.
|
|
*
|
|
* Currently, we do not release the lock acquired by ExecOpenScanRelation.
|
|
* This lock should be held till end of transaction. (There is a faction
|
|
* that considers this too much locking, however.)
|
|
*
|
|
* If we did want to release the lock, we'd have to repeat the logic in
|
|
* ExecOpenScanRelation in order to figure out what to release.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
void
|
|
ExecCloseScanRelation(Relation scanrel)
|
|
{
|
|
heap_close(scanrel, NoLock);
|
|
}
|
|
|
|
/*
|
|
* UpdateChangedParamSet
|
|
* Add changed parameters to a plan node's chgParam set
|
|
*/
|
|
void
|
|
UpdateChangedParamSet(PlanState *node, Bitmapset *newchg)
|
|
{
|
|
Bitmapset *parmset;
|
|
|
|
/*
|
|
* The plan node only depends on params listed in its allParam set. Don't
|
|
* include anything else into its chgParam set.
|
|
*/
|
|
parmset = bms_intersect(node->plan->allParam, newchg);
|
|
|
|
/*
|
|
* Keep node->chgParam == NULL if there's not actually any members; this
|
|
* allows the simplest possible tests in executor node files.
|
|
*/
|
|
if (!bms_is_empty(parmset))
|
|
node->chgParam = bms_join(node->chgParam, parmset);
|
|
else
|
|
bms_free(parmset);
|
|
}
|
|
|
|
/*
|
|
* executor_errposition
|
|
* Report an execution-time cursor position, if possible.
|
|
*
|
|
* This is expected to be used within an ereport() call. The return value
|
|
* is a dummy (always 0, in fact).
|
|
*
|
|
* The locations stored in parsetrees are byte offsets into the source string.
|
|
* We have to convert them to 1-based character indexes for reporting to
|
|
* clients. (We do things this way to avoid unnecessary overhead in the
|
|
* normal non-error case: computing character indexes would be much more
|
|
* expensive than storing token offsets.)
|
|
*/
|
|
int
|
|
executor_errposition(EState *estate, int location)
|
|
{
|
|
int pos;
|
|
|
|
/* No-op if location was not provided */
|
|
if (location < 0)
|
|
return 0;
|
|
/* Can't do anything if source text is not available */
|
|
if (estate == NULL || estate->es_sourceText == NULL)
|
|
return 0;
|
|
/* Convert offset to character number */
|
|
pos = pg_mbstrlen_with_len(estate->es_sourceText, location) + 1;
|
|
/* And pass it to the ereport mechanism */
|
|
return errposition(pos);
|
|
}
|
|
|
|
/*
|
|
* Register a shutdown callback in an ExprContext.
|
|
*
|
|
* Shutdown callbacks will be called (in reverse order of registration)
|
|
* when the ExprContext is deleted or rescanned. This provides a hook
|
|
* for functions called in the context to do any cleanup needed --- it's
|
|
* particularly useful for functions returning sets. Note that the
|
|
* callback will *not* be called in the event that execution is aborted
|
|
* by an error.
|
|
*/
|
|
void
|
|
RegisterExprContextCallback(ExprContext *econtext,
|
|
ExprContextCallbackFunction function,
|
|
Datum arg)
|
|
{
|
|
ExprContext_CB *ecxt_callback;
|
|
|
|
/* Save the info in appropriate memory context */
|
|
ecxt_callback = (ExprContext_CB *)
|
|
MemoryContextAlloc(econtext->ecxt_per_query_memory,
|
|
sizeof(ExprContext_CB));
|
|
|
|
ecxt_callback->function = function;
|
|
ecxt_callback->arg = arg;
|
|
|
|
/* link to front of list for appropriate execution order */
|
|
ecxt_callback->next = econtext->ecxt_callbacks;
|
|
econtext->ecxt_callbacks = ecxt_callback;
|
|
}
|
|
|
|
/*
|
|
* Deregister a shutdown callback in an ExprContext.
|
|
*
|
|
* Any list entries matching the function and arg will be removed.
|
|
* This can be used if it's no longer necessary to call the callback.
|
|
*/
|
|
void
|
|
UnregisterExprContextCallback(ExprContext *econtext,
|
|
ExprContextCallbackFunction function,
|
|
Datum arg)
|
|
{
|
|
ExprContext_CB **prev_callback;
|
|
ExprContext_CB *ecxt_callback;
|
|
|
|
prev_callback = &econtext->ecxt_callbacks;
|
|
|
|
while ((ecxt_callback = *prev_callback) != NULL)
|
|
{
|
|
if (ecxt_callback->function == function && ecxt_callback->arg == arg)
|
|
{
|
|
*prev_callback = ecxt_callback->next;
|
|
pfree(ecxt_callback);
|
|
}
|
|
else
|
|
prev_callback = &ecxt_callback->next;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Call all the shutdown callbacks registered in an ExprContext.
|
|
*
|
|
* The callback list is emptied (important in case this is only a rescan
|
|
* reset, and not deletion of the ExprContext).
|
|
*
|
|
* If isCommit is false, just clean the callback list but don't call 'em.
|
|
* (See comment for FreeExprContext.)
|
|
*/
|
|
static void
|
|
ShutdownExprContext(ExprContext *econtext, bool isCommit)
|
|
{
|
|
ExprContext_CB *ecxt_callback;
|
|
MemoryContext oldcontext;
|
|
|
|
/* Fast path in normal case where there's nothing to do. */
|
|
if (econtext->ecxt_callbacks == NULL)
|
|
return;
|
|
|
|
/*
|
|
* Call the callbacks in econtext's per-tuple context. This ensures that
|
|
* any memory they might leak will get cleaned up.
|
|
*/
|
|
oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
|
|
|
|
/*
|
|
* Call each callback function in reverse registration order.
|
|
*/
|
|
while ((ecxt_callback = econtext->ecxt_callbacks) != NULL)
|
|
{
|
|
econtext->ecxt_callbacks = ecxt_callback->next;
|
|
if (isCommit)
|
|
(*ecxt_callback->function) (ecxt_callback->arg);
|
|
pfree(ecxt_callback);
|
|
}
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
}
|
|
|
|
/*
|
|
* ExecLockNonLeafAppendTables
|
|
*
|
|
* Locks, if necessary, the tables indicated by the RT indexes contained in
|
|
* the partitioned_rels list. These are the non-leaf tables in the partition
|
|
* tree controlled by a given Append or MergeAppend node.
|
|
*/
|
|
void
|
|
ExecLockNonLeafAppendTables(List *partitioned_rels, EState *estate)
|
|
{
|
|
PlannedStmt *stmt = estate->es_plannedstmt;
|
|
ListCell *lc;
|
|
|
|
foreach(lc, partitioned_rels)
|
|
{
|
|
ListCell *l;
|
|
Index rti = lfirst_int(lc);
|
|
bool is_result_rel = false;
|
|
Oid relid = getrelid(rti, estate->es_range_table);
|
|
|
|
/* If this is a result relation, already locked in InitPlan */
|
|
foreach(l, stmt->nonleafResultRelations)
|
|
{
|
|
if (rti == lfirst_int(l))
|
|
{
|
|
is_result_rel = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Not a result relation; check if there is a RowMark that requires
|
|
* taking a RowShareLock on this rel.
|
|
*/
|
|
if (!is_result_rel)
|
|
{
|
|
PlanRowMark *rc = NULL;
|
|
|
|
foreach(l, stmt->rowMarks)
|
|
{
|
|
if (((PlanRowMark *) lfirst(l))->rti == rti)
|
|
{
|
|
rc = lfirst(l);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (rc && RowMarkRequiresRowShareLock(rc->markType))
|
|
LockRelationOid(relid, RowShareLock);
|
|
else
|
|
LockRelationOid(relid, AccessShareLock);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* GetAttributeByName
|
|
* GetAttributeByNum
|
|
*
|
|
* These functions return the value of the requested attribute
|
|
* out of the given tuple Datum.
|
|
* C functions which take a tuple as an argument are expected
|
|
* to use these. Ex: overpaid(EMP) might call GetAttributeByNum().
|
|
* Note: these are actually rather slow because they do a typcache
|
|
* lookup on each call.
|
|
*/
|
|
Datum
|
|
GetAttributeByName(HeapTupleHeader tuple, const char *attname, bool *isNull)
|
|
{
|
|
AttrNumber attrno;
|
|
Datum result;
|
|
Oid tupType;
|
|
int32 tupTypmod;
|
|
TupleDesc tupDesc;
|
|
HeapTupleData tmptup;
|
|
int i;
|
|
|
|
if (attname == NULL)
|
|
elog(ERROR, "invalid attribute name");
|
|
|
|
if (isNull == NULL)
|
|
elog(ERROR, "a NULL isNull pointer was passed");
|
|
|
|
if (tuple == NULL)
|
|
{
|
|
/* Kinda bogus but compatible with old behavior... */
|
|
*isNull = true;
|
|
return (Datum) 0;
|
|
}
|
|
|
|
tupType = HeapTupleHeaderGetTypeId(tuple);
|
|
tupTypmod = HeapTupleHeaderGetTypMod(tuple);
|
|
tupDesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
|
|
|
|
attrno = InvalidAttrNumber;
|
|
for (i = 0; i < tupDesc->natts; i++)
|
|
{
|
|
if (namestrcmp(&(tupDesc->attrs[i]->attname), attname) == 0)
|
|
{
|
|
attrno = tupDesc->attrs[i]->attnum;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (attrno == InvalidAttrNumber)
|
|
elog(ERROR, "attribute \"%s\" does not exist", attname);
|
|
|
|
/*
|
|
* heap_getattr needs a HeapTuple not a bare HeapTupleHeader. We set all
|
|
* the fields in the struct just in case user tries to inspect system
|
|
* columns.
|
|
*/
|
|
tmptup.t_len = HeapTupleHeaderGetDatumLength(tuple);
|
|
ItemPointerSetInvalid(&(tmptup.t_self));
|
|
tmptup.t_tableOid = InvalidOid;
|
|
tmptup.t_data = tuple;
|
|
|
|
result = heap_getattr(&tmptup,
|
|
attrno,
|
|
tupDesc,
|
|
isNull);
|
|
|
|
ReleaseTupleDesc(tupDesc);
|
|
|
|
return result;
|
|
}
|
|
|
|
Datum
|
|
GetAttributeByNum(HeapTupleHeader tuple,
|
|
AttrNumber attrno,
|
|
bool *isNull)
|
|
{
|
|
Datum result;
|
|
Oid tupType;
|
|
int32 tupTypmod;
|
|
TupleDesc tupDesc;
|
|
HeapTupleData tmptup;
|
|
|
|
if (!AttributeNumberIsValid(attrno))
|
|
elog(ERROR, "invalid attribute number %d", attrno);
|
|
|
|
if (isNull == NULL)
|
|
elog(ERROR, "a NULL isNull pointer was passed");
|
|
|
|
if (tuple == NULL)
|
|
{
|
|
/* Kinda bogus but compatible with old behavior... */
|
|
*isNull = true;
|
|
return (Datum) 0;
|
|
}
|
|
|
|
tupType = HeapTupleHeaderGetTypeId(tuple);
|
|
tupTypmod = HeapTupleHeaderGetTypMod(tuple);
|
|
tupDesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
|
|
|
|
/*
|
|
* heap_getattr needs a HeapTuple not a bare HeapTupleHeader. We set all
|
|
* the fields in the struct just in case user tries to inspect system
|
|
* columns.
|
|
*/
|
|
tmptup.t_len = HeapTupleHeaderGetDatumLength(tuple);
|
|
ItemPointerSetInvalid(&(tmptup.t_self));
|
|
tmptup.t_tableOid = InvalidOid;
|
|
tmptup.t_data = tuple;
|
|
|
|
result = heap_getattr(&tmptup,
|
|
attrno,
|
|
tupDesc,
|
|
isNull);
|
|
|
|
ReleaseTupleDesc(tupDesc);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Number of items in a tlist (including any resjunk items!)
|
|
*/
|
|
int
|
|
ExecTargetListLength(List *targetlist)
|
|
{
|
|
/* This used to be more complex, but fjoins are dead */
|
|
return list_length(targetlist);
|
|
}
|
|
|
|
/*
|
|
* Number of items in a tlist, not including any resjunk items
|
|
*/
|
|
int
|
|
ExecCleanTargetListLength(List *targetlist)
|
|
{
|
|
int len = 0;
|
|
ListCell *tl;
|
|
|
|
foreach(tl, targetlist)
|
|
{
|
|
TargetEntry *curTle = lfirst_node(TargetEntry, tl);
|
|
|
|
if (!curTle->resjunk)
|
|
len++;
|
|
}
|
|
return len;
|
|
}
|