granicus.if.org Git - postgresql/blob - src/include/executor/execdesc.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * execdesc.h
   4  *        plan and query descriptor accessor macros used by the executor
   5  *        and related modules.
   6  *
   7  *
   8  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
   9  * Portions Copyright (c) 1994, Regents of the University of California
  10  *
  11  * src/include/executor/execdesc.h
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15 #ifndef EXECDESC_H
  16 #define EXECDESC_H
  17
  18 #include "nodes/execnodes.h"
  19 #include "tcop/dest.h"
  20
  21
  22 /* ----------------
  23  *              query descriptor:
  24  *
  25  *      a QueryDesc encapsulates everything that the executor
  26  *      needs to execute the query.
  27  *
  28  *      For the convenience of SQL-language functions, we also support QueryDescs
  29  *      containing utility statements; these must not be passed to the executor
  30  *      however.
  31  * ---------------------
  32  */
  33 typedef struct QueryDesc
  34 {
  35         /* These fields are provided by CreateQueryDesc */
  36         CmdType         operation;              /* CMD_SELECT, CMD_UPDATE, etc. */
  37         PlannedStmt *plannedstmt;       /* planner's output (could be utility, too) */
  38         const char *sourceText;         /* source text of the query */
  39         Snapshot        snapshot;               /* snapshot to use for query */
  40         Snapshot        crosscheck_snapshot;    /* crosscheck for RI update/delete */
  41         DestReceiver *dest;                     /* the destination for tuple output */
  42         ParamListInfo params;           /* param values being passed in */
  43         QueryEnvironment *queryEnv; /* query environment passed in */
  44         int                     instrument_options; /* OR of InstrumentOption flags */
  45
  46         /* These fields are set by ExecutorStart */
  47         TupleDesc       tupDesc;                /* descriptor for result tuples */
  48         EState     *estate;                     /* executor's query-wide state */
  49         PlanState  *planstate;          /* tree of per-plan-node state */
  50
  51         /* This field is set by ExecutorRun */
  52         bool            already_executed;       /* true if previously executed */
  53
  54         /* This is always set NULL by the core system, but plugins can change it */
  55         struct Instrumentation *totaltime;      /* total time spent in ExecutorRun */
  56 } QueryDesc;
  57
  58 /* in pquery.c */
  59 extern QueryDesc *CreateQueryDesc(PlannedStmt *plannedstmt,
  60                                                                   const char *sourceText,
  61                                                                   Snapshot snapshot,
  62                                                                   Snapshot crosscheck_snapshot,
  63                                                                   DestReceiver *dest,
  64                                                                   ParamListInfo params,
  65                                                                   QueryEnvironment *queryEnv,
  66                                                                   int instrument_options);
  67
  68 extern void FreeQueryDesc(QueryDesc *qdesc);
  69
  70 #endif                                                  /* EXECDESC_H  */