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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bill Martin <bill.martin@communote.com>
cc: "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: Planner selects different execution plans depending on limit
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Comments: In-reply-to Bill Martin <bill.martin@communote.com>
	message dated "Thu, 13 Sep 2012 17:19:10 -0000"
Date: Thu, 13 Sep 2012 13:33:19 -0400
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Bill Martin <bill.martin@communote.com> writes:
> Tom Lane <tgl@sss.pgh.pa.us> writes:
>> He can do it without having to change his schema --- but it's the index
>> column, not the underlying content column, that needs its statistics
>> target adjusted.

> How can I adjust the statistics target of the index?

Just pretend it's a table.

	ALTER TABLE index_name ALTER COLUMN column_name SET STATISTICS ...

You'll need to look at the index (eg with \d) to see what the name of
the desired column is, since index expressions have system-assigned
column names.

			regards, tom lane