Skip site navigation (1) Skip section navigation (2)

Re: [PORTS] Port Bug Report: Suggestion: Allow users to specify optimizer hints or strategies.

From: Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
To: pjw(at)rhyme(dot)com(dot)au
Cc: pgsql-ports(at)postgreSQL(dot)org
Subject: Re: [PORTS] Port Bug Report: Suggestion: Allow users to specify optimizer hints or strategies.
Date: 1999-04-13 14:40:15
Message-ID: 199904131440.KAA13884@candle.pha.pa.us (view raw or flat)
Thread:
Lists: pgsql-ports
> Given the various complexities of the optimizer, would there be
> any way of allowing developers to specify strategy, or give
> hints. This is allowed in Dec (now Oracle) RDB, and in some
> fashion in both SQL/Server and Sybase.
> 
> The sorts of things that might be desirable are: which index to
> join on and the order of joining the tables.
> 
> Digital Equipment Corp used to maintain that the optimizer should
> know best, and that developers make more mistakes, and that is
> true. But an experienced DBA, along with details of common
> transactions, can almost always do better than an optimizer.

Usually hand-tuning joins is a symtom of a bad optimizer.  Rdb never had
a world-class optimizer, as far as I remember.

--
  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

pgsql-ports by date

Next:From: Bruce MomjianDate: 1999-04-13 14:43:21
Subject: Re: [PORTS] Port Bug Report: Tables, indexes...really owned by postgres are ghosted by other user
Previous:From: Unprivileged userDate: 1999-04-13 13:47:44
Subject: Port Bug Report:

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group