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) 2002-2023, PostgreSQL Global Development Group
   8  *
   9  * src/include/commands/prepare.h
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef PREPARE_H
  14 #define PREPARE_H
  15
  16 #include "commands/explain.h"
  17 #include "datatype/timestamp.h"
  18 #include "utils/plancache.h"
  19
  20 /*
  21  * The data structure representing a prepared statement.  This is now just
  22  * a thin veneer over a plancache entry --- the main addition is that of
  23  * a name.
  24  *
  25  * Note: all subsidiary storage lives in the referenced plancache entry.
  26  */
  27 typedef struct
  28 {
  29         /* dynahash.c requires key to be first field */
  30         char            stmt_name[NAMEDATALEN];
  31         CachedPlanSource *plansource;   /* the actual cached plan */
  32         bool            from_sql;               /* prepared via SQL, not FE/BE protocol? */
  33         TimestampTz prepare_time;       /* the time when the stmt was prepared */
  34 } PreparedStatement;
  35
  36
  37 /* Utility statements PREPARE, EXECUTE, DEALLOCATE, EXPLAIN EXECUTE */
  38 extern void PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
  39                                                  int stmt_location, int stmt_len);
  40 extern void ExecuteQuery(ParseState *pstate,
  41                                                  ExecuteStmt *stmt, IntoClause *intoClause,
  42                                                  ParamListInfo params,
  43                                                  DestReceiver *dest, QueryCompletion *qc);
  44 extern void DeallocateQuery(DeallocateStmt *stmt);
  45 extern void ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into,
  46                                                                 ExplainState *es, const char *queryString,
  47                                                                 ParamListInfo params, QueryEnvironment *queryEnv);
  48
  49 /* Low-level access to stored prepared statements */
  50 extern void StorePreparedStatement(const char *stmt_name,
  51                                                                    CachedPlanSource *plansource,
  52                                                                    bool from_sql);
  53 extern PreparedStatement *FetchPreparedStatement(const char *stmt_name,
  54                                                                                                  bool throwError);
  55 extern void DropPreparedStatement(const char *stmt_name, bool showError);
  56 extern TupleDesc FetchPreparedStatementResultDesc(PreparedStatement *stmt);
  57 extern List *FetchPreparedStatementTargetList(PreparedStatement *stmt);
  58
  59 extern void DropAllPreparedStatements(void);
  60
  61 #endif                                                  /* PREPARE_H */