From: AJ Weber <aweber@comcast.net>
To: pgsql-performance@postgresql.org
Subject: Analyze and default_statistics_target
Date: Mon, 21 Jan 2013 10:29:34 -0500
Message-ID: <50FD5EDE.8010002@comcast.net> (raw)
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I was under the impression that the default_statistics_target was a
percentage of rows to analyze. Maybe this is not the case?
I ran an analyze during a "quiet point" last night and for a few of my
large tables, I didn't get what I consider a reasonable sampling of
rows. When running with "verbose" enabled, it appeared that a maximum
of 240000 rows were being analyzed, including on tables exceeding 4-8mm
rows. My default_statistics_target = 80.
Shouldn't I be analyzing a larger percentage of these big tables?
What is the unit-of-measure used for default_statistics_target?
Thanks in advance,
AJ
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To: pgsql-performance@postgresql.org
Cc: aweber@comcast.net
Subject: Re: Analyze and default_statistics_target
In-Reply-To: <50FD5EDE.8010002@comcast.net>
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