From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tim Jones <TJones@optio.com>
Cc: Dave Dutcher <dave@tridecap.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: joining two tables slow due to sequential scan
Date: Fri, 10 Feb 2006 17:44:08 -0500
Message-ID: <2864.1139611448@sss.pgh.pa.us> (raw)
In-Reply-To: <47668A1334CDBF46927C1A0DFEB223D3131317@mail.optiosoftware.com>
References: <47668A1334CDBF46927C1A0DFEB223D3131317@mail.optiosoftware.com>
"Tim Jones" <TJones@optio.com> writes:
> QUERY PLAN
> 'Hash Join (cost=899.83..4384.17 rows=482 width=1350)'
> ' Hash Cond: ("outer".documentidentifier =
> "inner".dssdocumentidentifier)'
This is not EXPLAIN ANALYZE output. Also, the rowcount estimates
seem far enough off in the other query to make me wonder how long
it's been since you ANALYZEd the tables...
More generally, though, I don't see anything particularly wrong
with this query plan. You're selecting enough of the table that
an indexscan isn't necessarily a good plan.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, TJones@optio.com, dave@tridecap.com
Subject: Re: joining two tables slow due to sequential scan
In-Reply-To: <2864.1139611448@sss.pgh.pa.us>
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