106 lines
4.3 KiB
C
106 lines
4.3 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* spi_priv.h
|
|
* Server Programming Interface private declarations
|
|
*
|
|
* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
* src/include/executor/spi_priv.h
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#ifndef SPI_PRIV_H
|
|
#define SPI_PRIV_H
|
|
|
|
#include "executor/spi.h"
|
|
#include "utils/queryenvironment.h"
|
|
|
|
|
|
#define _SPI_PLAN_MAGIC 569278163
|
|
|
|
typedef struct
|
|
{
|
|
/* current results */
|
|
uint64 processed; /* by Executor */
|
|
SPITupleTable *tuptable; /* tuptable currently being built */
|
|
|
|
/* subtransaction in which current Executor call was started */
|
|
SubTransactionId execSubid;
|
|
|
|
/* resources of this execution context */
|
|
slist_head tuptables; /* list of all live SPITupleTables */
|
|
MemoryContext procCxt; /* procedure context */
|
|
MemoryContext execCxt; /* executor context */
|
|
MemoryContext savedcxt; /* context of SPI_connect's caller */
|
|
SubTransactionId connectSubid; /* ID of connecting subtransaction */
|
|
QueryEnvironment *queryEnv; /* query environment setup for SPI level */
|
|
|
|
/* transaction management support */
|
|
bool atomic; /* atomic execution context, does not allow
|
|
* transactions */
|
|
bool internal_xact; /* SPI-managed transaction boundary, skip
|
|
* cleanup */
|
|
|
|
/* saved values of API global variables for previous nesting level */
|
|
uint64 outer_processed;
|
|
SPITupleTable *outer_tuptable;
|
|
int outer_result;
|
|
} _SPI_connection;
|
|
|
|
/*
|
|
* SPI plans have three states: saved, unsaved, or temporary.
|
|
*
|
|
* Ordinarily, the _SPI_plan struct itself as well as the argtypes array
|
|
* are in a dedicated memory context identified by plancxt (which can be
|
|
* really small). All the other subsidiary state is in plancache entries
|
|
* identified by plancache_list (note: the list cells themselves are in
|
|
* plancxt).
|
|
*
|
|
* In an unsaved plan, the plancxt as well as the plancache entries' contexts
|
|
* are children of the SPI procedure context, so they'll all disappear at
|
|
* function exit. plancache.c also knows that the plancache entries are
|
|
* "unsaved", so it doesn't link them into its global list; hence they do
|
|
* not respond to inval events. This is OK since we are presumably holding
|
|
* adequate locks to prevent other backends from messing with the tables.
|
|
*
|
|
* For a saved plan, the plancxt is made a child of CacheMemoryContext
|
|
* since it should persist until explicitly destroyed. Likewise, the
|
|
* plancache entries will be under CacheMemoryContext since we tell
|
|
* plancache.c to save them. We rely on plancache.c to keep the cache
|
|
* entries up-to-date as needed in the face of invalidation events.
|
|
*
|
|
* There are also "temporary" SPI plans, in which the _SPI_plan struct is
|
|
* not even palloc'd but just exists in some function's local variable.
|
|
* The plancache entries are unsaved and exist under the SPI executor context,
|
|
* while additional data such as argtypes and list cells is loose in the SPI
|
|
* executor context. Such plans can be identified by having plancxt == NULL.
|
|
*
|
|
* We can also have "one-shot" SPI plans (which are typically temporary,
|
|
* as described above). These are meant to be executed once and discarded,
|
|
* and various optimizations are made on the assumption of single use.
|
|
* Note in particular that the CachedPlanSources within such an SPI plan
|
|
* are not "complete" until execution.
|
|
*
|
|
* Note: if the original query string contained only whitespace and comments,
|
|
* the plancache_list will be NIL and so there is no place to store the
|
|
* query string. We don't care about that, but we do care about the
|
|
* argument type array, which is why it's seemingly-redundantly stored.
|
|
*/
|
|
typedef struct _SPI_plan
|
|
{
|
|
int magic; /* should equal _SPI_PLAN_MAGIC */
|
|
bool saved; /* saved or unsaved plan? */
|
|
bool oneshot; /* one-shot plan? */
|
|
List *plancache_list; /* one CachedPlanSource per parsetree */
|
|
MemoryContext plancxt; /* Context containing _SPI_plan and data */
|
|
RawParseMode parse_mode; /* raw_parser() mode */
|
|
int cursor_options; /* Cursor options used for planning */
|
|
int nargs; /* number of plan arguments */
|
|
Oid *argtypes; /* Argument types (NULL if nargs is 0) */
|
|
ParserSetupHook parserSetup; /* alternative parameter spec method */
|
|
void *parserSetupArg;
|
|
} _SPI_plan;
|
|
|
|
#endif /* SPI_PRIV_H */
|