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Back out cleanup patch. Got old version and needs work.

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Neil Conway
This commit is contained in:
Bruce Momjian
2002-06-25 17:58:10 +00:00
parent ed275aea42
commit e2c007046f
13 changed files with 98 additions and 125 deletions
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12
src/backend/optimizer/path/costsize.c
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@@ -42,7 +42,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.86 2002/06/25 17:27:20 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.87 2002/06/25 17:58:10 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -154,11 +154,11 @@ cost_seqscan(Path *path, Query *root,
*
* Given a guesstimated cache size, we estimate the actual I/O cost per page
* with the entirely ad-hoc equations:
* if relpages >= effective_cache_size:
* random_page_cost * (1 - (effective_cache_size/relpages)/2)
* if relpages < effective_cache_size:
* 1 + (random_page_cost/2-1) * (relpages/effective_cache_size) ** 2
* These give the right asymptotic behavior (=> 1.0 as relpages becomes
* for rel_size <= effective_cache_size:
* 1 + (random_page_cost/2-1) * (rel_size/effective_cache_size) ** 2
* for rel_size >= effective_cache_size:
* random_page_cost * (1 - (effective_cache_size/rel_size)/2)
* These give the right asymptotic behavior (=> 1.0 as rel_size becomes
* small, => random_page_cost as it becomes large) and meet in the middle
* with the estimate that the cache is about 50% effective for a relation
* of the same size as effective_cache_size. (XXX this is probably all

17
src/backend/optimizer/prep/_deadcode/prepkeyset.c
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@@ -1,7 +1,7 @@
/*-------------------------------------------------------------------------
*
* prepkeyset.c
* Special preparation for keyset queries (KSQO).
* Special preperation for keyset queries.
*
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
@@ -14,6 +14,12 @@
#include "postgres.h"
#include "optimizer/planmain.h"
/*
* Node_Copy
* a macro to simplify calling of copyObject on the specified field
*/
#define Node_Copy(from, newnode, field) newnode->field = copyObject(from->field)
bool _use_keyset_query_optimizer = FALSE;
#ifdef ENABLE_KEY_SET_QUERY
@@ -49,20 +55,13 @@ static int TotalExpr;
* a HAVING, or a GROUP BY. It must be a single table and have KSQO
* set to 'on'.
*
* The primary use of this transformation is to avoid the exponential
* The primary use of this transformation is to avoid the exponrntial
* memory consumption of cnfify() and to make use of index access
* methods.
*
* daveh@insightdist.com 1998-08-31
*
* May want to also prune out duplicate terms.
*
* XXX: this code is currently not compiled because it has not been
* updated to work with the re-implementation of UNION/INTERSECT/EXCEPT
* in PostgreSQL 7.1. However, it is of questionable value in any
* case, because it changes the semantics of the original query:
* UNION will add an implicit SELECT DISTINCT, which might change
* the results that are returned.
**********************************************************************/
void
transformKeySetQuery(Query *origNode)