Re: Shortcutting too-large offsets? - Mailing list pgsql-performance

From Josh Berkus
Subject Re: Shortcutting too-large offsets?
Date
Msg-id 4E860E09.7090107@agliodbs.com
Whole thread Raw
In response to Re: Shortcutting too-large offsets?  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Shortcutting too-large offsets?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
Tom,

> In principle, yeah, we could make it do that, but it seems like a likely
> source of maintenance headaches.  This example is not exactly compelling
> enough to make me want to do it.  Large OFFSETs are always going to be
> problematic from a performance standpoint, and the fact that we could
> short-circuit this one corner case isn't really going to make them much
> more usable.

It's not that uncommon of a corner case though; it's one which happens
all the time in webapps which paginate.  People just have to ask for a
page after the end.  It's really a question of how simple the code to
make the optimization would be; if it would be a 5-line patch, then it's
worth it; if it would be a 110-line refactor, no.

Lemme see if I can figure it out ...

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com

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