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

Re: Performance and IN clauses

From: Matthew Wakeling <matthew(at)flymine(dot)org>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Performance and IN clauses
Date: 2008-11-18 16:12:24
Message-ID: alpine.DEB.1.10.0811181610310.4666@aragorn.flymine.org (view raw or flat)
Thread:
Lists: pgsql-performance
On Tue, 18 Nov 2008, Kynn Jones wrote:
> Also, assuming that the optimal way to write the query depends on the length of $node_list, how can I estimate the
> "critical length" at which I should switch from one form of the query to the other?

In the past, I have found the fastest way to do this was to operate on 
groups of a bit less than a thousand values, and issue one query per 
group. Of course, Postgres may have improved since then, so I'll let more 
knowledgable people cover that for me.

Matthew

-- 
 Heat is work, and work's a curse. All the heat in the universe, it's
 going to cool down, because it can't increase, then there'll be no
 more work, and there'll be perfect peace.      -- Michael Flanders

In response to

Responses

pgsql-performance by date

Next:From: tvDate: 2008-11-18 16:38:45
Subject: Re: Performance and IN clauses
Previous:From: Kynn JonesDate: 2008-11-18 15:53:19
Subject: Performance and IN clauses

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