Re: : Column Performance in a query - Mailing list pgsql-performance

From Ondrej Ivanič
Subject Re: : Column Performance in a query
Date
Msg-id CAM6mie+5VSj2kmk3cNbjb4eY-S9NcX_xH3dCzHHMvHWnH6Sn+w@mail.gmail.com
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In response to : Column Performance in a query  (Venkat Balaji <venkat.balaji@verse.in>)
List pgsql-performance
Hi,

On 4 October 2011 21:25, Venkat Balaji <venkat.balaji@verse.in> wrote:
> I got hold of two catalog tables "pg_stats" and "pg_class".
> Column "avg_width" and "distinct" in pg_stats gets me lot of sensible
> information regarding, column values and size of the column.
> Can someone help me know when the values in these columns are bound to
> change ? Is it only when ANALYZE runs ?

yes, ANALYZE updates underlaying pg_statistic table.

--
Ondrej Ivanic
(ondrej.ivanic@gmail.com)

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