Re: vacuum, performance, and MVCC

On Thu, 2006-06-22 at 13:42 -0400, Jonah H. Harris wrote:
> On 6/22/06, Rod Taylor <pg@rbt.ca> wrote:
> > If you INSERT into multiple partitions (by time -- say one per minute)
> > and TRUNCATE periodically (30 minute old partitions for 30 minute
> > expiry) it works much better. Expiring the session is quite fast as well
> > since they'll go away with the truncate.
> 
> Forgive me if this sounds rude because I'm not meaning it as such, but
> this suggestion sounds like a MySQL-ish hack.  No doubt it would work,
> but should an application-writer have to incur the cost of writing
> something different because the database can't handle it?  I remember
> having to write subselect code in PHP because MySQL couldn't do it...
> not what I would call a *solution* by any mean.

Application writer doesn't need to do anything. That's what rules,
views, etc. are for.

The only snag is that PostgreSQL doesn't 'eliminate' a partition by
itself, so the truncate is a manual requirement.

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