Re: Sequential scan from simple query

On Wednesday 23. May 2007 16:31, Leif B. Kristensen wrote:
>I've also tried:
>
>pgslekt=> create index last_edit_key on persons(last_edit);
>
>But that doesn't make any difference.

But this one did:

pgslekt=> create index last_edited_persons_key on
persons(last_edit,person_id);
CREATE INDEX
pgslekt=> explain select person_id, last_edit from persons
               order by last_edit desc, person_id desc limit 50;
                                                 QUERY PLAN
-------------------------------------------------------------------
 Limit  (cost=0.00..3.81 rows=50 width=8)
   ->  Index Scan Backward using last_edited_persons_key on persons
(cost=0.00..1230.10 rows=16123 width=8)
(2 rows)

Doh ...
--
Leif Biberg Kristensen | Registered Linux User #338009
http://solumslekt.org/ | Cruising with Gentoo/KDE
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