From:
Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
To:
taral(at)mail(dot)utexas(dot)edu (Taral)
Cc:
daveh(at)insightdist(dot)com, ser(at)nsu(dot)ru, pgsql-general(at)postgreSQL(dot)org
Subject:
Re: [GENERAL] Long update query ?
Date:
1998-10-01 22:54:19
Message-ID:
199810012254.SAA18974@candle.pha.pa.us (view raw or flat )
Thread:
1998-09-27 09:20:35 from "Sergei Chernev" <ser(at)nsu(dot)ru>
1998-09-28 13:21:08 from David Hartwig <daveh(at)insightdist(dot)com>
1998-09-28 17:15:01 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-01 22:54:19 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-01 23:45:33 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 02:18:29 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 05:35:12 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 06:02:48 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 16:37:15 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 16:40:56 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 16:47:48 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 17:31:18 from jwieck(at)debis(dot)com (Jan Wieck)
1998-10-02 17:58:25 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 21:12:19 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 21:39:05 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 21:49:26 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-02 21:57:15 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 22:04:24 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-03 03:01:07 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-04 01:57:30 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-04 02:26:20 from "Taral" <taral(at)mail(dot)utexas(dot)edu>
1998-10-04 03:32:14 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-05 14:33:37 from David Hartwig <daveh(at)insightdist(dot)com>
1998-10-06 02:23:13 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-06 15:28:22 from David Hartwig <daveh(at)insightdist(dot)com>
1998-10-07 02:41:21 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-07 17:56:18 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-07 20:34:15 from David Hartwig <daveh(at)insightdist(dot)com>
1998-10-07 21:33:07 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
1998-10-02 17:40:39 from Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
Lists:
pgsql-general pgsql-hackers
[Charset iso-8859-1 unsupported, filtering to ASCII...]
> > This is caused by a semi-well known weakness in the optimizer.
> > The optimizer
> > rewrites the WHERE clause in conjunctive normal form (CNF):
> >
> > (A and B) or (C and D) ==> (A or C) and (A or D) and (B or C)
> > and (B or D)
> >
>
> Wouldn't disjunctive normal form be better, since it can be implemented as
> the simple union of a set of small queries?
Please tell us more.
--
Bruce Momjian | http://www.op.net/~candle
maillist(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
In response to
Responses
pgsql-hackers by date
Next :From: Bruce MomjianDate: 1998-10-01 22:58:39Subject : Re: [HACKERS] Proper cleanup at backend exitPrevious :From : Bruce MomjianDate : 1998-10-01 22:51:49Subject : Re: [HACKERS] Little parser question
pgsql-general by date
Next :From: TaralDate: 1998-10-01 23:45:33Subject : Re: [GENERAL] Long update query ? (also Re: [GENERAL] CNF vs. DNF)Previous :From : Anand SureliaDate : 1998-10-01 22:34:10Subject : Help SPI
