From: Jeremy Haile <jhaile@fastmail.fm>
To: Chad Wagner <chad.wagner@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: PG8.2.1 choosing slow seqscan over idx scan
Date: Wed, 17 Jan 2007 13:46:40 -0500
Message-ID: <1169059600.23210.1169763553@webmail.messagingengine.com> (raw)
In-Reply-To: <81961ff50701170926r3dd41f39u9e2d4a131b3c3097@mail.gmail.com>
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> It would be nice if the database could
> learn to estimate these values, as newer versions of Oracle does.
That would be really nice since it would take some of the guess work out
of it.
> Yes, cluster would rebuild the table for you. I wouldn't do anything too
> intrusive, run with the random_page_cost lowered, perhaps vacuum full,
> reindex, and see what happens.
I'll try doing the vacuum full and reindex tonight since they require
exclusive locks.
> Yep, my thoughts exactly. Partitioning support is PostgreSQL is there,
> but it needs a bit more of a tighter integration into the core (I shouldn't
> have to create a view, n tables, n rules, etc). Additionally, I have read
> that at some point when you have "y" partitions the performance degrades,
> haven't really looked into it myself.
Yeah - I haven't setup partitioning in PostgreSQL before, although I've
read quite a bit about it. I've talked about getting improved syntax
for partitioning in PostgreSQL. MySQL's syntax is much simpler and more
intuitive compared to setting them up with Postgres - it would be nice
if PostgreSQL adopted a similar syntax where partitions were first-class
citizens.
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To: pgsql-performance@postgresql.org
Cc: jhaile@fastmail.fm, chad.wagner@gmail.com, tgl@sss.pgh.pa.us
Subject: Re: PG8.2.1 choosing slow seqscan over idx scan
In-Reply-To: <1169059600.23210.1169763553@webmail.messagingengine.com>
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