Re: WIP: Collecting statistics on CSV file data - Mailing list pgsql-hackers

From David Fetter
Subject Re: WIP: Collecting statistics on CSV file data
Date
Msg-id 20110921002232.GA18333@fetter.org
Whole thread Raw
In response to Re: WIP: Collecting statistics on CSV file data  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: WIP: Collecting statistics on CSV file data
List pgsql-hackers
On Tue, Sep 20, 2011 at 11:13:05AM -0400, Tom Lane wrote:
> Marti Raudsepp <marti@juffo.org> writes:
> > 2011/9/12 Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>:
> >> This is called when ANALYZE command is executed. (ANALYZE
> >> command should be executed because autovacuum does not analyze foreign
> >> tables.)
> 
> > This is a good idea.
> 
> > However, if adding these statistics requires an explicit ANALYZE
> > command, then we should also have a command for resetting the
> > collected statistics -- to get it back into the un-analyzed state.
> 
> Uh, why?  There is no UNANALYZE operation for ordinary tables, and
> I've never heard anyone ask for one.
> 
> If you're desperate you could manually delete the relevant rows in
> pg_statistic, a solution that would presumably work for foreign tables
> too.
> 
> Probably a more interesting question is why we wouldn't change
> autovacuum so that it calls this automatically for foreign tables.

How about a per-table setting that tells autovacuum whether to do
this?  Come to think of it, all of per-FDW, per-remote and per-table
settings would be handy, so people could express things like, "all CSV
files except these three, all PostgreSQL connections on the
10.1.0.0/16 network, and these two tables in Oracle."

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com
iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics

Remember to vote!
Consider donating to Postgres: http://www.postgresql.org/about/donate


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: EXPLAIN and nfiltered, take two
Next
From: Tom Lane
Date:
Subject: Isolation tests still falling over routinely