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Tid access method feature from Hiroshi Inoue, Inoue@tpf.co.jp

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This commit is contained in:
Bruce Momjian
1999-11-23 20:07:06 +00:00
parent 54ffd4677a
commit 6f9ff92cc0
28 changed files with 1396 additions and 32 deletions
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26
src/backend/optimizer/path/costsize.c
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@@ -18,7 +18,7 @@
* Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.45 1999/08/22 20:14:41 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.46 1999/11/23 20:06:54 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -59,6 +59,7 @@ bool _enable_sort_ = true;
bool _enable_nestloop_ = true;
bool _enable_mergejoin_ = true;
bool _enable_hashjoin_ = true;
bool _enable_tidscan_ = true;
Cost _cpu_page_weight_ = _CPU_PAGE_WEIGHT_;
Cost _cpu_index_page_weight_ = _CPU_INDEX_PAGE_WEIGHT_;
@@ -174,6 +175,29 @@ cost_index(Oid indexid,
return temp;
}
/*
* cost_tidscan
* Determines and returns the cost of scanning a relation using tid-s.
*
* disk = number of tids
* cpu = *CPU-PAGE-WEIGHT* * number_of_tids
*
* Returns a flonum.
*
*/
Cost
cost_tidscan(List *tideval)
{
Cost temp = 0;
if (!_enable_tidscan_)
temp += _disable_cost_;
temp += (1.0 + _cpu_page_weight_) * length(tideval);
return temp;
}
/*
* cost_sort
* Determines and returns the cost of sorting a relation by considering