Message-ID: <457FE568.8010302@freesurf.fr>
Date: Wed, 13 Dec 2006 12:35:04 +0100
From: Arnaud Lesauvage <thewild@freesurf.fr>
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To: Ragnar <gnari@hive.is>
CC: pgsql-performance@postgresql.org
Subject: Re: Slow update with simple query
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Ragnar a écrit :
>> Do you think the problem is with the indexes ?
> 
> I guess so. are you sure about the index on t1.uid?
> what are the column definitions for t1.uid and t2.uid ?
> are they the same ?

Man, no !!!
I just checked and indeed, no index on this column. I probably dropped 
it lately.
Thanks Ragnar.
(t1.uid and t2.uid were the same, character(32) columns)

> you should ba able to get a plan similar to:
> Merge Join  (cost=0.00..43.56 rows=1000 width=11)
>    Merge Cond: ("outer".uid = "inner".uid)
>    ->  Index Scan using t1i on t1  (cost=0.00..38298.39 rows=2000035
> width=10)
>    ->  Index Scan using t2i on t2  (cost=0.00..26.73 rows=1000 width=5)
> 
> what postgres version are you using ?

Ooops, forgot that too : 8.1.4

I am creating the index right now, I'll tell you if this fixes the problem.
Thanks for your help !

--
Arnaud