postgresql/src/include/optimizer/planner.h

/*-------------------------------------------------------------------------
 *
 * planner.h
 *	  prototypes for planner.c.
 *
 *
 * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * $PostgreSQL: pgsql/src/include/optimizer/planner.h,v 1.35 2006/03/05 15:58:57 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#ifndef PLANNER_H
#define PLANNER_H

#include "nodes/params.h"
#include "nodes/parsenodes.h"
#include "nodes/plannodes.h"


extern ParamListInfo PlannerBoundParamList;		/* current boundParams */

extern Plan *planner(Query *parse, bool isCursor, int cursorOptions,
		ParamListInfo boundParams);
extern Plan *subquery_planner(Query *parse, double tuple_fraction,
				 List **subquery_pathkeys);

#endif   /* PLANNER_H */
Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 08:22:35 +02:00			`/*-------------------------------------------------------------------------`
			`*`
Change my-function-name-- to my_function_name, and optimizer renames. 1999-02-14 00:22:53 +01:00			`* planner.h`
Massive commit to run PGINDENT on all .c and .h files. 1997-09-07 07:04:48 +02:00			`* prototypes for planner.c.`
Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 08:22:35 +02:00			`*`
			`*`
Update copyright for 2006. Update scripts. 2006-03-05 16:59:11 +01:00			`* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group`
Add: * Portions Copyright (c) 1996-2000, PostgreSQL, Inc to all files copyright Regents of Berkeley. Man, that's a lot of files. 2000-01-26 06:58:53 +01:00			`* Portions Copyright (c) 1994, Regents of the University of California`
Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 08:22:35 +02:00			`*`
Update copyright for 2006. Update scripts. 2006-03-05 16:59:11 +01:00			`* $PostgreSQL: pgsql/src/include/optimizer/planner.h,v 1.35 2006/03/05 15:58:57 momjian Exp $`
Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 08:22:35 +02:00			`*`
			`*-------------------------------------------------------------------------`
			`*/`
			`#ifndef PLANNER_H`
			`#define PLANNER_H`

When using extended-query protocol, postpone planning of unnamed statements until Bind is received, so that actual parameter values are visible to the planner. Make use of the parameter values for estimation purposes (but don't fold them into the actual plan). This buys back most of the potential loss of plan quality that ensues from using out-of-line parameters instead of putting literal values right into the query text. This patch creates a notion of constant-folding expressions 'for estimation purposes only', in which case we can be more aggressive than the normal eval_const_expressions() logic can be. Right now the only difference in behavior is inserting bound values for Params, but it will be interesting to look at other possibilities. One that we've seen come up repeatedly is reducing now() and related functions to current values, so that queries like ... WHERE timestampcol > now() - '1 day' have some chance of being planned effectively. Oliver Jowett, with some kibitzing from Tom Lane. 2004-06-11 03:09:22 +02:00			`#include "nodes/params.h"`
Cleanup up include files. 1997-11-26 02:14:33 +01:00			`#include "nodes/parsenodes.h"`
			`#include "nodes/plannodes.h"`
Break parser functions into smaller files, group together. 1997-11-25 23:07:18 +01:00
Move pg_checkretval out of the planner (where it never belonged) into pg_proc.c (where it's actually used). Fix it to correctly handle tlists that contain resjunk target items, and improve error messages. This addresses bug reported by Krupnikov 6-July-00. 2000-08-21 22:55:31 +02:00
Pgindent run for 8.0. 2004-08-29 07:07:03 +02:00			`extern ParamListInfo PlannerBoundParamList; /* current boundParams */`
When using extended-query protocol, postpone planning of unnamed statements until Bind is received, so that actual parameter values are visible to the planner. Make use of the parameter values for estimation purposes (but don't fold them into the actual plan). This buys back most of the potential loss of plan quality that ensues from using out-of-line parameters instead of putting literal values right into the query text. This patch creates a notion of constant-folding expressions 'for estimation purposes only', in which case we can be more aggressive than the normal eval_const_expressions() logic can be. Right now the only difference in behavior is inserting bound values for Params, but it will be interesting to look at other possibilities. One that we've seen come up repeatedly is reducing now() and related functions to current values, so that queries like ... WHERE timestampcol > now() - '1 day' have some chance of being planned effectively. Oliver Jowett, with some kibitzing from Tom Lane. 2004-06-11 03:09:22 +02:00
			`extern Plan planner(Query parse, bool isCursor, int cursorOptions,`
Pgindent run for 8.0. 2004-08-29 07:07:03 +02:00			`ParamListInfo boundParams);`
Remove planner's private fields from Query struct, and put them into a new PlannerInfo struct, which is passed around instead of the bare Query in all the planning code. This commit is essentially just a code-beautification exercise, but it does open the door to making larger changes to the planner data structures without having to muck with the widely-known Query struct. 2005-06-06 00:32:58 +02:00			`extern Plan subquery_planner(Query parse, double tuple_fraction,`
Standard pgindent run for 8.1. 2005-10-15 04:49:52 +02:00			`List **subquery_pathkeys);`
Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 08:22:35 +02:00
New pgindent run with fixes suggested by Tom. Patch manually reviewed, initdb/regression tests pass. 2001-11-05 18:46:40 +01:00			`#endif /* PLANNER_H */`