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

Re: not sorted clustered index (8.2)

From: Stefan Kaltenbrunner <stefan(at)kaltenbrunner(dot)cc>
To: Adriaan van Kekem <avkekem(at)gmail(dot)com>
Cc: pgsql-bugs(at)postgresql(dot)org
Subject: Re: not sorted clustered index (8.2)
Date: 2007-11-05 09:51:41
Message-ID: 472EE7AD.20402@kaltenbrunner.cc (view raw or flat)
Thread:
Lists: pgsql-bugs
Adriaan van Kekem wrote:
> hi,
> 
> As part of the definition of a clustered index, the default sort of a 
> table is based on the clustered index. In our application sometimes we 
> see that the sort is invalid. Our table is like:
> iid identity (clustered primary key)
> data varchar
> if we do a query like:
> select * from table where iid in (1,2,3)
> 
> we suspect that we get the result based on the iid, but sometimes this 
> is not happening. Is this a known issue?
> our configuration is postgresql 8.2 on ubuntu

this is not a bug - your application should not depend on a particular 
sort order without using ORDER BY.
That this works in other RDBMS is an artefact of their implementation 
and you should probably not rely on that (and keep in mind that 
clustering is a on-time operation in postgresql so modifications to the 
table will change the ordering again)


Stefan

In response to

pgsql-bugs by date

Next:From: M. PalmDate: 2007-11-05 16:19:01
Subject: BUG #3720: wrong results at using ltree
Previous:From: Adriaan van KekemDate: 2007-11-05 09:39:37
Subject: not sorted clustered index (8.2)

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