Re: PROPOSAL: tracking aggregated numbers from pg_stat_database

On Sat, Apr 13, 2013 at 9:01 AM, Peter Eisentraut <peter_e@gmx.net> wrote:
> On Sat, 2013-04-06 at 21:51 +0200, Tomas Vondra wrote:
>> This more or less works in stable environments, but once you start
>> dropping databases (think of hosting with shared DB server) it gets
>> unusable because after DROP DATABASE the database suddenly disappears
>> from the sum.
>>
>> Therefore I do propose tracking the aggregated stats, similar to the
>> pg_stat_bgwriter view.
>
> It seems like this will open a can of worms.  Maybe someone wants
> aggregated stats for pg_stat_user_tables?  Or maybe instead of the sum,
> someone wants to track the average?  etc.  I don't think we should turn
> the statistics collector into a poor man's data warehouse or statistics
> engine.  Couldn't you transfer the data to some other system for
> long-term analysis?  Maybe you could even use event triggers to have
> DROP DATABASE do that automatically.

I think Tomas's point about objects getting dropped is a pretty fair
one, although I agree there are potential cans of worms here.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company