rdelaage
/
postgresql
mirror of https://git.postgresql.org/git/postgresql.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
postgresql/src/include/optimizer/tlist.h

38 lines
1.2 KiB
C
Raw Normal View History

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
* tlist.h
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
* prototypes for tlist.c.
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*
Update CVS HEAD for 2007 copyright. Back branches are typically not back-stamped for this.
2007-01-05 23:20:05 +01:00
* Portions Copyright (c) 1996-2007, 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
*
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
* $PostgreSQL: pgsql/src/include/optimizer/tlist.h,v 1.48 2007/11/15 21:14:44 momjian Exp $
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
*
*-------------------------------------------------------------------------
*/
#ifndef TLIST_H
#define TLIST_H
Cleanup up include files.
1997-11-26 02:14:33 +01:00
#include "nodes/relation.h"
Restructure building of join relation targetlists so that a join plan node emits only those vars that are actually needed above it in the plan tree. (There were comments in the code suggesting that this was done at some point in the dim past, but for a long time we have just made join nodes emit everything that either input emitted.) Aside from being marginally more efficient, this fixes the problem noted by Peter Eisentraut where a join above an IN-implemented-as-join might fail, because the subplan targetlist constructed in the latter case didn't meet the expectation of including everything. Along the way, fix some places that were O(N^2) in the targetlist length. This is not all the trouble spots for wide queries by any means, but it's a step forward.
2003-06-30 01:05:05 +02:00
Merge Resdom nodes into TargetEntry nodes to simplify code and save a few palloc's. I also chose to eliminate the restype and restypmod fields entirely, since they are redundant with information stored in the node's contained expression; re-examining the expression at need seems simpler and more reliable than trying to keep restype/restypmod up to date. initdb forced due to change in contents of stored rules.
2005-04-06 18:34:07 +02:00
extern TargetEntry *tlist_member(Node *node, List *targetlist);
Last week's patch for make_sort_from_pathkeys wasn't good enough: it has to be able to discard top-level RelabelType nodes on *both* sides of the equivalence-class-to-target-list comparison, since make_pathkey_from_sortinfo might either add or remove a RelabelType. Also fix the latter to do the removal case cleanly. Per example from Peter.
2007-11-08 20:25:37 +01:00
extern TargetEntry *tlist_member_ignore_relabel(Node *node, List *targetlist);
Postgres95 1.01 Distribution - Virgin Sources
1996-07-09 08:22:35 +02:00
Used modified version of indent that understands over 100 typedefs.
1997-09-08 23:56:23 +02:00
extern List *flatten_tlist(List *tlist);
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
extern List *add_to_flat_tlist(List *tlist, List *vars);
Massive commit to run PGINDENT on all *.c and *.h files.
1997-09-07 07:04:48 +02:00
Fix EquivalenceClass code to handle volatile sort expressions in a more predictable manner; in particular that if you say ORDER BY output-column-ref, it will in fact sort by that specific column even if there are multiple syntactic matches. An example is SELECT random() AS a, random() AS b FROM ... ORDER BY b, a; While the use-case for this might be a bit debatable, it worked as expected in earlier releases, so we should preserve the behavior for 8.3. Per my recent proposal. While at it, fix convert_subquery_pathkeys() to handle RelabelType stripping in both directions; it needs this for the same reasons make_sort_from_pathkeys does.
2007-11-08 22:49:48 +01:00
extern TargetEntry *get_sortgroupref_tle(Index sortref,
pgindent run for 8.3.
2007-11-15 22:14:46 +01:00
List *targetList);
Redesign DISTINCT ON as discussed in pgsql-sql 1/25/00: syntax is now SELECT DISTINCT ON (expr [, expr ...]) targetlist ... and there is a check to make sure that the user didn't specify an ORDER BY that's incompatible with the DISTINCT operation. Reimplement nodeUnique and nodeGroup to use the proper datatype-specific equality function for each column being compared --- they used to do bitwise comparisons or convert the data to text strings and strcmp(). (To add insult to injury, they'd look up the conversion functions once for each tuple...) Parse/plan representation of DISTINCT is now a list of SortClause nodes. initdb forced by querytree change...
2000-01-27 19:11:50 +01:00
extern TargetEntry *get_sortgroupclause_tle(SortClause *sortClause,
Ye-old pgindent run. Same 4-space tabs.
2000-04-12 19:17:23 +02:00
List *targetList);
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
extern Node *get_sortgroupclause_expr(SortClause *sortClause,
Ye-old pgindent run. Same 4-space tabs.
2000-04-12 19:17:23 +02:00
List *targetList);
IN clauses appearing at top level of WHERE can now be handled as joins. There are two implementation techniques: the executor understands a new JOIN_IN jointype, which emits at most one matching row per left-hand row, or the result of the IN's sub-select can be fed through a DISTINCT filter and then joined as an ordinary relation. Along the way, some minor code cleanup in the optimizer; notably, break out most of the jointree-rearrangement preprocessing in planner.c and put it in a new file prep/prepjointree.c.
2003-01-20 19:55:07 +01:00
extern List *get_sortgrouplist_exprs(List *sortClauses,
pgindent run.
2003-08-04 02:43:34 +02:00
List *targetList);
Another pgindent run. Fixes enum indenting, and improves #endif spacing. Also adds space for one-line comments.
2001-10-28 07:26:15 +01:00
Teach planner to convert simple UNION ALL subqueries into append relations, thereby sharing code with the inheritance case. This puts the UNION-ALL-view approach to partitioned tables on par with inheritance, so far as constraint exclusion is concerned: it works either way. (Still need to update the docs to say so.) The definition of "simple UNION ALL" is a little simpler than I would like --- basically the union arms can only be SELECT * FROM foo --- but it's good enough for partitioned-table cases.
2006-02-03 22:08:49 +01:00
extern bool tlist_same_datatypes(List *tlist, List *colTypes, bool junkOK);
New pgindent run with fixes suggested by Tom. Patch manually reviewed, initdb/regression tests pass.
2001-11-05 18:46:40 +01:00
#endif /* TLIST_H */