From: Tom Lane <tgl@sss.pgh.pa.us>
To: Joe Conway <mail@joeconway.com>
Cc: Stephan Szabo <sszabo@megazone.bigpanda.com>
Cc: Dani Oderbolz <oderbolz@ecologic.de>
Cc: pgsql-hackers@postgresql.org
Subject: Re: [SQL] "SELECT IN" Still Broken in 7.4b
Date: Thu, 21 Aug 2003 18:17:55 -0400
Message-ID: <29873.1061504275@sss.pgh.pa.us> (raw)
In-Reply-To: <3F45414A.6030301@joeconway.com>
References: <20030821102627.C51705-100000@megazone.bigpanda.com>
<25062.1061498540@sss.pgh.pa.us>
<3F45414A.6030301@joeconway.com>
Joe Conway <mail@joeconway.com> writes:
> Tom Lane wrote:
>> I'm toying with the notion of ripping out that logic and instead
>> building an in-memory hashtable of already-returned TIDs. This could
>> theoretically run out of memory if the multiple indexscan returns enough
>> tuples, but I think in practice that wouldn't happen because the planner
>> wouldn't choose an indexscan when very large numbers of tuples are being
>> selected.
> I thought with your recent changes, you could use dynahash, which
> already spills to disk instead of consuming all memory?
I was going to use dynahash, but it doesn't spill to disk. You're
confusing that with the HashJoin mechanism, which is quite different and
only really useful for joins.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, mail@joeconway.com, sszabo@megazone.bigpanda.com, oderbolz@ecologic.de, pgsql-hackers@postgresql.org
Subject: Re: [SQL] "SELECT IN" Still Broken in 7.4b
In-Reply-To: <29873.1061504275@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox