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To: justin <jtyme@intrusic.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Serialized Transaction Locking Issues 
In-reply-to: <3E403A3E.5020508@intrusic.com> 
References: <3E403A3E.5020508@intrusic.com>
Comments: In-reply-to justin <jtyme@intrusic.com>
	message dated "Tue, 04 Feb 2003 17:10:06 -0500"
Date: Tue, 04 Feb 2003 18:21:28 -0500
Message-ID: <18900.1044400888@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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justin <jtyme@intrusic.com> writes:
> I'm currently in the midst of working on a serializable transaction 
> which drops indexes on several tables, does a bulk copy, and rebuilds 
> the indexes. Based on what I've read it seemed as though I'd be able to 
> concurrently execute read only queries against these tables,

Nope, because "drop index" obtains an exclusive lock on the table.
(If it didn't, some other query might try to *use* the index, which
would create a bit of a problem if the DROP committed midway through.)

			regards, tom lane