Re: Interpreting statistics collector output - Mailing list pgsql-general

From Steve Madsen
Subject Re: Interpreting statistics collector output
Date
Msg-id 15EE8605-CBE8-4334-B76F-D93CE18232B6@lightyearsoftware.com
Whole thread Raw
In response to Re: Interpreting statistics collector output  (Decibel! <decibel@decibel.org>)
Responses Re: Interpreting statistics collector output
List pgsql-general
On Aug 8, 2007, at 6:08 PM, Decibel! wrote:
> Something else I like to look at is pg_stat_all_tables seq_scan and
> seq_tup_read. If seq_scan is a large number and seq_tup_read/
> seq_scan is
> also large, that indicates that you could use an index on that table.

If seq_tup_read / seq_scan is large relative to the number of rows in
the table, wouldn't that imply that those sequential scans are often
returning most of the rows in the table?  In that case, would an
index help much or is a sequential scan the expected result?

--
Steve Madsen <steve@lightyearsoftware.com>
Light Year Software, LLC  http://lightyearsoftware.com
ZingLists: Stay organized, and share lists online.  http://zinglists.com



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