Re: PG writes a lot to the disk

In response to "Laurent Raufaste" <analogue(at)glop(dot)org>:

> 2008/3/21, Gregory Stark <stark(at)enterprisedb(dot)com>:
> >
> > Well that's true it does. But only once per row. So analyze would have set the
> > bit on every row. You could do the same thing with something ligter like
> > "select count(*) from <table>".
>
> Well, the table has been analyzed, I did SELECT, PG write on the
> table. That's a fact.
>
> But it's also true (I juste tested it) that every file of a table is
> modified by a SELECT COUNT.

The real question (to verify Tom's point) is does a _second_ SELECT count()
modify the table again? If so, then something else is going on than
what Tom suggested.

--
Bill Moran
Collaborative Fusion Inc.
http://people.collaborativefusion.com/~wmoran/

wmoran(at)collaborativefusion(dot)com
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