From: Robins Tharakan <robins@pobox.com>
To: pgsql-performance@postgresql.org
Subject: Re: Performance across multiple schemas
Date: Wed, 29 Aug 2007 07:20:51 +0530
Message-ID: <36af4bed0708281850v5348da17y97b7df2e696262e9@mail.gmail.com> (raw)
In-Reply-To: <23414.1188308966@sss.pgh.pa.us>
References: <36af4bed0708280605j5448ac52of6f7dc08791f0ab2@mail.gmail.com>
<23414.1188308966@sss.pgh.pa.us>
Thanks Tom,
Exactly what I did, when I realised that there was an extra Table in the
FROM with no conditions set.
Well anyway, this did clear my doubts about whether schema affects
performance at all.
Robins
On 8/28/07, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
>
> Schemas are utterly, utterly irrelevant to performance.
>
> I'm guessing you missed analyzing one of the tables, or forgot an index,
> or something like that. Also, if you did anything "cute" like use the
> same table name in more than one schema, you need to check the
> possibility that some query is selecting the wrong one of the tables.
>
> The explain output you showed is no help because the expense is
> evidently down inside one of the functions in the SELECT output list.
>
> One thing you should probably try before getting too frantic is
> re-ANALYZEing all the tables and then starting a fresh session to
> clear any cached plans inside the functions. If it's still slow
> then it'd be worth digging deeper.
>
> regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: robins@pobox.com
Subject: Re: Performance across multiple schemas
In-Reply-To: <36af4bed0708281850v5348da17y97b7df2e696262e9@mail.gmail.com>
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