Re: ALTER TABLE SET STATISTICS requires AccessExclusiveLock

On Mon, 2009-10-19 at 12:56 -0300, Alvaro Herrera wrote:
> Simon Riggs wrote:
> > 
> > On Fri, 2009-08-07 at 15:58 -0400, Alvaro Herrera wrote:
> > > Tom Lane wrote:
> > > > Peter Eisentraut <peter_e@gmx.net> writes:
> > > > > Is there a good reason for $subject, other than that the code is entangled 
> > > > > with other ALTER TABLE code?
> > > > 
> > > > I think it could be lower, but it would take nontrivial restructuring of
> > > > the ALTER TABLE support.  In particular, consider what happens when you
> > > > have a list of subcommands that don't all require the same lock level.
> > > > I think you'd need to scan the list and find the highest required lock
> > > > level before starting ...
> > > 
> > > IIRC there was a patch from Simon to address this issue, but it had some
> > > holes which he didn't have time to close, so it sank.  Maybe this can be
> > > resurrected and fixed.
> > 
> > I was intending to finish that patch in this release cycle.
> 
> Since you're busy with Hot Standby, any chance you could pass it on?

If you'd like. It's mostly finished, just one last thing to finish:
atomic changes to pg_class via an already agreed API.

-- Simon Riggs           www.2ndQuadrant.com