granicus.if.org Git - postgresql/blob - src/include/commands/prepare.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * prepare.h
   4  *        PREPARE, EXECUTE and DEALLOCATE commands, and prepared-stmt storage
   5  *
   6  *
   7  * Copyright (c) 2002-2003, PostgreSQL Global Development Group
   8  *
   9  * $Id: prepare.h,v 1.8 2003/08/08 21:42:40 momjian Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef PREPARE_H
  14 #define PREPARE_H
  15
  16 #include "executor/executor.h"
  17 #include "nodes/parsenodes.h"
  18 #include "tcop/dest.h"
  19
  20
  21 /*
  22  * The data structure representing a prepared statement
  23  *
  24  * Note: all subsidiary storage lives in the context denoted by the context
  25  * field.  However, the string referenced by commandTag is not subsidiary
  26  * storage; it is assumed to be a compile-time-constant string.  As with
  27  * portals, commandTag shall be NULL if and only if the original query string
  28  * (before rewriting) was an empty string.
  29  */
  30 typedef struct
  31 {
  32         /* dynahash.c requires key to be first field */
  33         char            stmt_name[NAMEDATALEN];
  34         char       *query_string;       /* text of query, or NULL */
  35         const char *commandTag;         /* command tag (a constant!), or NULL */
  36         List       *query_list;         /* list of queries */
  37         List       *plan_list;          /* list of plans */
  38         List       *argtype_list;       /* list of parameter type OIDs */
  39         MemoryContext context;          /* context containing this query */
  40 } PreparedStatement;
  41
  42
  43 /* Utility statements PREPARE, EXECUTE, DEALLOCATE, EXPLAIN EXECUTE */
  44 extern void PrepareQuery(PrepareStmt *stmt);
  45 extern void ExecuteQuery(ExecuteStmt *stmt, DestReceiver *dest);
  46 extern void DeallocateQuery(DeallocateStmt *stmt);
  47 extern void ExplainExecuteQuery(ExplainStmt *stmt, TupOutputState *tstate);
  48
  49 /* Low-level access to stored prepared statements */
  50 extern void StorePreparedStatement(const char *stmt_name,
  51                                            const char *query_string,
  52                                            const char *commandTag,
  53                                            List *query_list,
  54                                            List *plan_list,
  55                                            List *argtype_list);
  56 extern PreparedStatement *FetchPreparedStatement(const char *stmt_name,
  57                                            bool throwError);
  58 extern void DropPreparedStatement(const char *stmt_name, bool showError);
  59 extern List *FetchPreparedStatementParams(const char *stmt_name);
  60 extern TupleDesc FetchPreparedStatementResultDesc(PreparedStatement *stmt);
  61
  62 #endif   /* PREPARE_H */