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Reimplement nodeMaterial to use a temporary BufFile (or even memory, if the

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materialized tupleset is small enough) instead of a temporary relation.
This was something I was thinking of doing anyway for performance, and Jan
says he needs it for TOAST because he doesn't want to cope with toasting
noname relations.  With this change, the 'noname table' support in heap.c
is dead code, and I have accordingly removed it.  Also clean up 'noname'
plan handling in planner --- nonames are either sort or materialize plans,
and it seems less confusing to handle them separately under those names.
This commit is contained in:
Tom Lane
2000-06-18 22:44:35 +00:00
parent 2c0edb3c86
commit 1ee26b7764
32 changed files with 1090 additions and 982 deletions
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43
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 1.61 2000/05/31 00:28:22 petere Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.62 2000/06/18 22:44:06 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -55,10 +55,15 @@
#include "miscadmin.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/internal.h"
#include "utils/lsyscache.h"
/*
* The length of a variable-length field in bytes (stupid estimate...)
*/
#define _DEFAULT_ATTRIBUTE_WIDTH_ 12
#define LOG2(x) (log(x) / 0.693147180559945)
#define LOG6(x) (log(x) / 1.79175946922805)
@@ -114,29 +119,17 @@ cost_seqscan(Path *path, RelOptInfo *baserel)
if (!enable_seqscan)
startup_cost += disable_cost;
/* disk costs */
if (lfirsti(baserel->relids) < 0)
{
/*
* cost of sequentially scanning a materialized temporary relation
*/
run_cost += _NONAME_SCAN_COST_;
}
else
{
/*
* The cost of reading a page sequentially is 1.0, by definition.
* Note that the Unix kernel will typically do some amount of
* read-ahead optimization, so that this cost is less than the
* true cost of reading a page from disk. We ignore that issue
* here, but must take it into account when estimating the cost of
* non-sequential accesses!
*/
run_cost += baserel->pages; /* sequential fetches with cost
* 1.0 */
}
/*
* disk costs
*
* The cost of reading a page sequentially is 1.0, by definition.
* Note that the Unix kernel will typically do some amount of
* read-ahead optimization, so that this cost is less than the
* true cost of reading a page from disk. We ignore that issue
* here, but must take it into account when estimating the cost of
* non-sequential accesses!
*/
run_cost += baserel->pages; /* sequential fetches with cost 1.0 */
/* CPU costs */
cpu_per_tuple = cpu_tuple_cost + baserel->baserestrictcost;