From: Tom Lane <tgl@sss.pgh.pa.us>
To: Joshua D. Drake <jd@commandprompt.com>
Cc: Scott Marlowe <scott.marlowe@gmail.com>
Cc: Peter Koczan <pjkoczan@gmail.com>
Cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: disabling an index without deleting it?
Date: Tue, 26 Feb 2008 17:22:40 -0500
Message-ID: <9050.1204064560@sss.pgh.pa.us> (raw)
In-Reply-To: <20080226130339.64bd4ec3@commandprompt.com>
References: <4544e0330802261246t574167fdpc47629d1bbe64fed@mail.gmail.com>
<dcc563d10802261257h6abfbc92x62a7569b8610ecc4@mail.gmail.com>
<20080226130339.64bd4ec3@commandprompt.com>
"Joshua D. Drake" <jd@commandprompt.com> writes:
> "Scott Marlowe" <scott.marlowe@gmail.com> wrote:
>> begin;
>> drop index abc_dx;
>> select ....
>> rollback;
>>
>> and viola, your index is still there. note that there are likely some
>> locking issues with this, so be careful with it in production. But on
>> a test box it's a very easy way to test various indexes.
> Wouldn't you also bloat the index?
No, what makes you think that? The index won't change at all in the
above example. The major problem is, as Scott says, that DROP INDEX
takes exclusive lock on the table so any other sessions will be locked
out of it for the duration of your test query.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, jd@commandprompt.com, scott.marlowe@gmail.com, pjkoczan@gmail.com
Subject: Re: disabling an index without deleting it?
In-Reply-To: <9050.1204064560@sss.pgh.pa.us>
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