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postgresql/src/include/optimizer/planmain.h

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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
* planmain.h
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
* prototypes for various files in optimizer/plan
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*
Update copyrights in source tree to 2008.
2008-01-01 20:46:01 +01:00
* Portions Copyright (c) 1996-2008, 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
*
Fix a couple of oversights associated with the "physical tlist" optimization: we had several code paths where a physical tlist could be used for the input to a Sort node, which is a dumb idea because any unneeded table columns will increase the volume of data the sort has to push around. (Unfortunately the easy-looking fix of calling disuse_physical_tlist during make_sort_xxx doesn't work because in most cases we're already committed to the current input tlist --- it's been marked with sort column numbers, or we've built grouping column numbers using it, etc. The tlist has to be selected properly at the calling level before we start constructing sort-col information. This is easy enough to do, we were just failing to take the point into consideration.) Back-patch to 8.3. I believe the problem probably exists clear back to 7.4 when the physical tlist optimization was added, but I'm afraid to back-patch further than 8.3 without a great deal more study than I want to put into it. The code in this area has drifted a lot over time. The real-world importance of these code paths is uncertain anyway --- I think in many cases we'd probably prefer hash-based methods.
2008-04-17 23:22:14 +02:00
* $PostgreSQL: pgsql/src/include/optimizer/planmain.h,v 1.107 2008/04/17 21:22:14 tgl Exp $
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*-------------------------------------------------------------------------
*/
#ifndef PLANMAIN_H
#define PLANMAIN_H
Cleanup up include files.
1997-11-26 02:14:33 +01:00
#include "nodes/plannodes.h"
#include "nodes/relation.h"
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
/*
* prototypes for plan/planmain.c
*/
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 void query_planner(PlannerInfo *root, List *tlist,
Teach tuplesort.c about "top N" sorting, in which only the first N tuples need be returned. We keep a heap of the current best N tuples and sift-up new tuples into it as we scan the input. For M input tuples this means only about M*log(N) comparisons instead of M*log(M), not to mention a lot less workspace when N is small --- avoiding spill-to-disk for large M is actually the most attractive thing about it. Patch includes planner and executor support for invoking this facility in ORDER BY ... LIMIT queries. Greg Stark, with some editorialization by moi.
2007-05-04 03:13:45 +02:00
double tuple_fraction, double limit_tuples,
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
Path **cheapest_path, Path **sorted_path,
double *num_groups);
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
Create the planner mechanism for optimizing simple MIN and MAX queries into indexscans on matching indexes. For the moment, it only handles int4 and text datatypes; next step is to add a column to pg_aggregate so that all MIN/MAX aggregates can be handled. Per my recent proposal.
2005-04-12 01:06:57 +02:00
/*
* prototypes for plan/planagg.c
*/
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 *optimize_minmax_aggregates(PlannerInfo *root, List *tlist,
Standard pgindent run for 8.1.
2005-10-15 04:49:52 +02:00
Path *best_path);
Create the planner mechanism for optimizing simple MIN and MAX queries into indexscans on matching indexes. For the moment, it only handles int4 and text datatypes; next step is to add a column to pg_aggregate so that all MIN/MAX aggregates can be handled. Per my recent proposal.
2005-04-12 01:06:57 +02:00
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
/*
* prototypes for plan/createplan.c
*/
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 *create_plan(PlannerInfo *root, Path *best_path);
Reimplementation of UNION/INTERSECT/EXCEPT. INTERSECT/EXCEPT now meet the SQL92 semantics, including support for ALL option. All three can be used in subqueries and views. DISTINCT and ORDER BY work now in views, too. This rewrite fixes many problems with cross-datatype UNIONs and INSERT/SELECT where the SELECT yields different datatypes than the INSERT needs. I did that by making UNION subqueries and SELECT in INSERT be treated like subselects-in-FROM, thereby allowing an extra level of targetlist where the datatype conversions can be inserted safely. INITDB NEEDED!
2000-10-05 21:11:39 +02:00
extern SubqueryScan *make_subqueryscan(List *qptlist, List *qpqual,
Turn the rangetable used by the executor into a flat list, and avoid storing useless substructure for its RangeTblEntry nodes. (I chose to keep using the same struct node type and just zero out the link fields for unneeded info, rather than making a separate ExecRangeTblEntry type --- it seemed too fragile to have two different rangetable representations.) Along the way, put subplans into a list in the toplevel PlannedStmt node, and have SubPlan nodes refer to them by list index instead of direct pointers. Vadim wanted to do that years ago, but I never understood what he was on about until now. It makes things a *whole* lot more robust, because we can stop worrying about duplicate processing of subplans during expression tree traversals. That's been a constant source of bugs, and it's finally gone. There are some consequent simplifications yet to be made, like not using a separate EState for subplans in the executor, but I'll tackle that later.
2007-02-22 23:00:26 +01:00
Index scanrelid, Plan *subplan, List *subrtable);
Restructure handling of inheritance queries so that they work with outer joins, and clean things up a good deal at the same time. Append plan node no longer hacks on rangetable at runtime --- instead, all child tables are given their own RT entries during planning. Concept of multiple target tables pushed up into execMain, replacing bug-prone implementation within nodeAppend. Planner now supports generating Append plans for inheritance sets either at the top of the plan (the old way) or at the bottom. Expanding at the bottom is appropriate for tables used as sources, since they may appear inside an outer join; but we must still expand at the top when the target of an UPDATE or DELETE is an inheritance set, because we actually need a different targetlist and junkfilter for each target table in that case. Fortunately a target table can't be inside an outer join... Bizarre mutual recursion between union_planner and prepunion.c is gone --- in fact, union_planner doesn't really have much to do with union queries anymore, so I renamed it grouping_planner.
2000-11-12 01:37:02 +01:00
extern Append *make_append(List *appendplans, bool isTarget, List *tlist);
Refactor planner's pathkeys data structure to create a separate, explicit representation of equivalence classes of variables. This is an extensive rewrite, but it brings a number of benefits: * planner no longer fails in the presence of "incomplete" operator families that don't offer operators for every possible combination of datatypes. * avoid generating and then discarding redundant equality clauses. * remove bogus assumption that derived equalities always use operators named "=". * mergejoins can work with a variety of sort orders (e.g., descending) now, instead of tying each mergejoinable operator to exactly one sort order. * better recognition of redundant sort columns. * can make use of equalities appearing underneath an outer join.
2007-01-20 21:45:41 +01:00
extern Sort *make_sort_from_pathkeys(PlannerInfo *root, Plan *lefttree,
Teach tuplesort.c about "top N" sorting, in which only the first N tuples need be returned. We keep a heap of the current best N tuples and sift-up new tuples into it as we scan the input. For M input tuples this means only about M*log(N) comparisons instead of M*log(M), not to mention a lot less workspace when N is small --- avoiding spill-to-disk for large M is actually the most attractive thing about it. Patch includes planner and executor support for invoking this facility in ORDER BY ... LIMIT queries. Greg Stark, with some editorialization by moi.
2007-05-04 03:13:45 +02:00
List *pathkeys, double limit_tuples);
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 Sort *make_sort_from_sortclauses(PlannerInfo *root, List *sortcls,
When testing whether a sub-plan can do projection, use a general-purpose check instead of hardwiring assumptions that only certain plan node types can appear at the places where we are testing. This was always a pretty fragile assumption, and it turns out to be broken in 7.4 for certain cases involving IN-subselect tests that need type coercion. Also, modify code that builds finished Plan tree so that node types that don't do projection always copy their input node's targetlist, rather than having the tlist passed in from the caller. The old method makes it too easy to write broken code that thinks it can modify the tlist when it cannot.
2004-01-18 01:50:03 +01:00
Plan *lefttree);
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 Sort *make_sort_from_groupcols(PlannerInfo *root, List *groupcls,
pgindent run.
2003-08-04 02:43:34 +02:00
AttrNumber *grpColIdx, Plan *lefttree);
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 Agg *make_agg(PlannerInfo *root, List *tlist, List *qual,
pgindent run.
2003-08-04 02:43:34 +02:00
AggStrategy aggstrategy,
Change the planner-to-executor API so that the planner tells the executor which comparison operators to use for plan nodes involving tuple comparison (Agg, Group, Unique, SetOp). Formerly the executor looked up the default equality operator for the datatype, which was really pretty shaky, since it's possible that the data being fed to the node is sorted according to some nondefault operator class that could have an incompatible idea of equality. The planner knows what it has sorted by and therefore can provide the right equality operator to use. Also, this change moves a couple of catalog lookups out of the executor and into the planner, which should help startup time for pre-planned queries by some small amount. Modify the planner to remove some other cavalier assumptions about always being able to use the default operators. Also add "nulls first/last" info to the Plan node for a mergejoin --- neither the executor nor the planner can cope yet, but at least the API is in place.
2007-01-10 19:06:05 +01:00
int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators,
pgindent run.
2003-08-04 02:43:34 +02:00
long numGroups, int numAggs,
Plan *lefttree);
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 Group *make_group(PlannerInfo *root, List *tlist, List *qual,
Change the planner-to-executor API so that the planner tells the executor which comparison operators to use for plan nodes involving tuple comparison (Agg, Group, Unique, SetOp). Formerly the executor looked up the default equality operator for the datatype, which was really pretty shaky, since it's possible that the data being fed to the node is sorted according to some nondefault operator class that could have an incompatible idea of equality. The planner knows what it has sorted by and therefore can provide the right equality operator to use. Also, this change moves a couple of catalog lookups out of the executor and into the planner, which should help startup time for pre-planned queries by some small amount. Modify the planner to remove some other cavalier assumptions about always being able to use the default operators. Also add "nulls first/last" info to the Plan node for a mergejoin --- neither the executor nor the planner can cope yet, but at least the API is in place.
2007-01-10 19:06:05 +01:00
int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators,
pgindent run.
2003-08-04 02:43:34 +02:00
double numGroups,
Plan *lefttree);
Restructure parsetree representation of DECLARE CURSOR: now it's a utility statement (DeclareCursorStmt) with a SELECT query dangling from it, rather than a SELECT query with a few unusual fields in it. Add code to determine whether a planned query can safely be run backwards. If DECLARE CURSOR specifies SCROLL, ensure that the plan can be run backwards by adding a Materialize plan node if it can't. Without SCROLL, you get an error if you try to fetch backwards from a cursor that can't handle it. (There is still some discussion about what the exact behavior should be, but this is necessary infrastructure in any case.) Along the way, make EXPLAIN DECLARE CURSOR work.
2003-03-10 04:53:52 +01:00
extern Plan *materialize_finished_plan(Plan *subplan);
When testing whether a sub-plan can do projection, use a general-purpose check instead of hardwiring assumptions that only certain plan node types can appear at the places where we are testing. This was always a pretty fragile assumption, and it turns out to be broken in 7.4 for certain cases involving IN-subselect tests that need type coercion. Also, modify code that builds finished Plan tree so that node types that don't do projection always copy their input node's targetlist, rather than having the tlist passed in from the caller. The old method makes it too easy to write broken code that thinks it can modify the tlist when it cannot.
2004-01-18 01:50:03 +01:00
extern Unique *make_unique(Plan *lefttree, List *distinctList);
Fix up LIMIT/OFFSET planning so that we cope with non-constant LIMIT or OFFSET clauses by using estimate_expression_value(). The main advantage of this is that if the expression is a Param and we have a value for the Param, we'll use that value rather than defaulting. Also, fix some thinkos in the logic for combining LIMIT/OFFSET with an externally supplied tuple fraction (this covers cases like EXISTS(...LIMIT...)). And make sure the results of all this are shown by EXPLAIN. Per a gripe from Merlin Moncure.
2005-08-18 19:51:12 +02:00
extern Limit *make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
Change LIMIT/OFFSET to use int8 Dhanaraj M
2006-07-26 02:34:48 +02:00
int64 offset_est, int64 count_est);
When testing whether a sub-plan can do projection, use a general-purpose check instead of hardwiring assumptions that only certain plan node types can appear at the places where we are testing. This was always a pretty fragile assumption, and it turns out to be broken in 7.4 for certain cases involving IN-subselect tests that need type coercion. Also, modify code that builds finished Plan tree so that node types that don't do projection always copy their input node's targetlist, rather than having the tlist passed in from the caller. The old method makes it too easy to write broken code that thinks it can modify the tlist when it cannot.
2004-01-18 01:50:03 +01:00
extern SetOp *make_setop(SetOpCmd cmd, Plan *lefttree,
pgindent run. Make it all clean.
2001-03-22 05:01:46 +01:00
List *distinctList, AttrNumber flagColIdx);
Turn the rangetable used by the executor into a flat list, and avoid storing useless substructure for its RangeTblEntry nodes. (I chose to keep using the same struct node type and just zero out the link fields for unneeded info, rather than making a separate ExecRangeTblEntry type --- it seemed too fragile to have two different rangetable representations.) Along the way, put subplans into a list in the toplevel PlannedStmt node, and have SubPlan nodes refer to them by list index instead of direct pointers. Vadim wanted to do that years ago, but I never understood what he was on about until now. It makes things a *whole* lot more robust, because we can stop worrying about duplicate processing of subplans during expression tree traversals. That's been a constant source of bugs, and it's finally gone. There are some consequent simplifications yet to be made, like not using a separate EState for subplans in the executor, but I'll tackle that later.
2007-02-22 23:00:26 +01:00
extern Result *make_result(PlannerInfo *root, List *tlist,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
Node *resconstantqual, Plan *subplan);
When testing whether a sub-plan can do projection, use a general-purpose check instead of hardwiring assumptions that only certain plan node types can appear at the places where we are testing. This was always a pretty fragile assumption, and it turns out to be broken in 7.4 for certain cases involving IN-subselect tests that need type coercion. Also, modify code that builds finished Plan tree so that node types that don't do projection always copy their input node's targetlist, rather than having the tlist passed in from the caller. The old method makes it too easy to write broken code that thinks it can modify the tlist when it cannot.
2004-01-18 01:50:03 +01:00
extern bool is_projection_capable_plan(Plan *plan);
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
/*
* prototypes for plan/initsplan.c
*/
Teach planner how to rearrange join order for some classes of OUTER JOIN. Per my recent proposal. I ended up basing the implementation on the existing mechanism for enforcing valid join orders of IN joins --- the rules for valid outer-join orders are somewhat similar.
2005-12-20 03:30:36 +01:00
extern int from_collapse_limit;
extern int join_collapse_limit;
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 void add_base_rels_to_query(PlannerInfo *root, Node *jtnode);
extern void build_base_rel_tlists(PlannerInfo *root, List *final_tlist);
Keep the planner from failing on "WHERE false AND something IN (SELECT ...)". eval_const_expressions simplifies this to just "WHERE false", but we have already done pull_up_IN_clauses so the IN join will be done, or at least planned, anyway. The trouble case comes when the sub-SELECT is itself a join and we decide to implement the IN by unique-ifying the sub-SELECT outputs: with no remaining reference to the output Vars in WHERE, we won't have propagated the Vars up to the upper join point, leading to "variable not found in subplan target lists" error. Fix by adding an extra scan of in_info_list and forcing all Vars mentioned therein to be propagated up to the IN join point. Per bug report from Miroslav Sulc.
2007-10-04 22:44:47 +02:00
extern void add_IN_vars_to_tlists(PlannerInfo *root);
Refactor planner's pathkeys data structure to create a separate, explicit representation of equivalence classes of variables. This is an extensive rewrite, but it brings a number of benefits: * planner no longer fails in the presence of "incomplete" operator families that don't offer operators for every possible combination of datatypes. * avoid generating and then discarding redundant equality clauses. * remove bogus assumption that derived equalities always use operators named "=". * mergejoins can work with a variety of sort orders (e.g., descending) now, instead of tying each mergejoinable operator to exactly one sort order. * better recognition of redundant sort columns. * can make use of equalities appearing underneath an outer join.
2007-01-20 21:45:41 +01:00
extern void add_vars_to_targetlist(PlannerInfo *root, List *vars,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
Relids where_needed);
Teach planner how to rearrange join order for some classes of OUTER JOIN. Per my recent proposal. I ended up basing the implementation on the existing mechanism for enforcing valid join orders of IN joins --- the rules for valid outer-join orders are somewhat similar.
2005-12-20 03:30:36 +01:00
extern List *deconstruct_jointree(PlannerInfo *root);
Refactor planner's pathkeys data structure to create a separate, explicit representation of equivalence classes of variables. This is an extensive rewrite, but it brings a number of benefits: * planner no longer fails in the presence of "incomplete" operator families that don't offer operators for every possible combination of datatypes. * avoid generating and then discarding redundant equality clauses. * remove bogus assumption that derived equalities always use operators named "=". * mergejoins can work with a variety of sort orders (e.g., descending) now, instead of tying each mergejoinable operator to exactly one sort order. * better recognition of redundant sort columns. * can make use of equalities appearing underneath an outer join.
2007-01-20 21:45:41 +01:00
extern void distribute_restrictinfo_to_rels(PlannerInfo *root,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
RestrictInfo *restrictinfo);
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 void process_implied_equality(PlannerInfo *root,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
Oid opno,
Expr *item1,
Expr *item2,
Relids qualscope,
bool below_outer_join,
bool both_const);
Refactor planner's pathkeys data structure to create a separate, explicit representation of equivalence classes of variables. This is an extensive rewrite, but it brings a number of benefits: * planner no longer fails in the presence of "incomplete" operator families that don't offer operators for every possible combination of datatypes. * avoid generating and then discarding redundant equality clauses. * remove bogus assumption that derived equalities always use operators named "=". * mergejoins can work with a variety of sort orders (e.g., descending) now, instead of tying each mergejoinable operator to exactly one sort order. * better recognition of redundant sort columns. * can make use of equalities appearing underneath an outer join.
2007-01-20 21:45:41 +01:00
extern RestrictInfo *build_implied_join_equality(Oid opno,
Expr *item1,
Expr *item2,
Relids qualscope);
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
/*
* prototypes for plan/setrefs.c
*/
Re-run pgindent with updated list of typedefs. (Updated README should avoid this problem in the future.)
2007-11-15 23:25:18 +01:00
extern Plan *set_plan_references(PlannerGlobal *glob,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
Plan *plan,
List *rtable);
Re-run pgindent with updated list of typedefs. (Updated README should avoid this problem in the future.)
2007-11-15 23:25:18 +01:00
extern List *set_returning_clause_references(PlannerGlobal *glob,
Fix the plan-invalidation mechanism to treat regclass constants that refer to a relation as a reason to invalidate a plan when the relation changes. This handles scenarios such as dropping/recreating a sequence that is referenced by nextval('seq') in a cached plan. Rather than teach plancache.c all about digging through plan trees to find regclass Consts, we charge the planner's setrefs.c with making a list of the relation OIDs on which each plan depends. That way the list can be built cheaply during a plan tree traversal that has to happen anyway. Per bug #3662 and subsequent discussion.
2007-10-11 20:05:27 +02:00
List *rlist,
Add INSERT/UPDATE/DELETE RETURNING, with basic docs and regression tests. plpgsql support to come later. Along the way, convert execMain's SELECT INTO support into a DestReceiver, in order to eliminate some ugly special cases. Jonah Harris and Tom Lane
2006-08-12 04:52:06 +02:00
Plan *topplan,
Index resultRelation);
Phase 2 of read-only-plans project: restructure expression-tree nodes so that all executable expression nodes inherit from a common supertype Expr. This is somewhat of an exercise in code purity rather than any real functional advance, but getting rid of the extra Oper or Func node formerly used in each operator or function call should provide at least a little space and speed improvement. initdb forced by changes in stored-rules representation.
2002-12-12 16:49:42 +01:00
extern void fix_opfuncids(Node *node);
Another pgindent run with updated typedefs.
2003-08-08 23:42:59 +02:00
extern void set_opfuncid(OpExpr *opexpr);
Add COST and ROWS options to CREATE/ALTER FUNCTION, plus underlying pg_proc columns procost and prorows, to allow simple user adjustment of the estimated cost of a function call, as well as control of the estimated number of rows returned by a set-returning function. We might eventually wish to extend this to allow function-specific estimation routines, but there seems to be consensus that we should try a simple constant estimate first. In particular this provides a relatively simple way to control the order in which different WHERE clauses are applied in a plan node, which is a Good Thing in view of the fact that the recent EquivalenceClass planner rewrite made that much less predictable than before.
2007-01-22 02:35:23 +01:00
extern void set_sa_opfuncid(ScalarArrayOpExpr *opexpr);
Major revision of sort-node handling: push knowledge of query sort order down into planner, instead of handling it only at the very top level of the planner. This fixes many things. An explicit sort is now avoided if there is a cheaper alternative (typically an indexscan) not only for ORDER BY, but also for the internal sort of GROUP BY. It works even when there is no other reason (such as a WHERE condition) to consider the indexscan. It works for indexes on functions. It works for indexes on functions, backwards. It's just so cool... CAUTION: I have changed the representation of SortClause nodes, therefore THIS UPDATE BREAKS STORED RULES. You will need to initdb.
1999-08-21 05:49:17 +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 /* PLANMAIN_H */