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Re: Offset

From: David Wheeler <david(at)wheeler(dot)net>
To: Stephan Szabo <sszabo(at)megazone(dot)bigpanda(dot)com>
Cc: <sfpug(at)postgresql(dot)org>
Subject: Re: Offset
Date: 2003-08-28 19:47:49
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Lists: sfpug
On Thursday, August 28, 2003, at 11:58  AM, Stephan Szabo wrote:

>> It calls them "derived tables", which makes sense to me. Couldn't see
> One question is whether or not they can have limit clauses applied to
> them in the query expression, but they probably can.

Yeah, and they use the same keywords, which I applaud. Not that it 
matters, since Bricolage hasn't been ported yet.

> Looks like 7.2 supports queries of that form from trying against our
> unused 7.2 server here.

Oh, good. I have no trouble bumping the requirement up to 7.2. 7.1 is 
ancient history already.

> Performance-wise it should be pretty reasonable since the query plan
> for that section basically becomes
>  Subquery Scan
>   Limit
>    <Normal Scan>
> where the limit and subquery scan should be nearly free.  And, it save 
> you
> from having to join rows that you're not actually using.

Excellent. Many thanks again, Stephan.



David Wheeler                                     AIM: dwTheory
david(at)kineticode(dot)com                              ICQ: 15726394                     Yahoo!: dew7e
                                                Jabber: Theory(at)jabber(dot)org
Kineticode. Setting knowledge in motion.[sm]

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  • Re: Offset at 2003-08-28 18:58:47 from Stephan Szabo

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