Re: Patch: plan invalidation vs stored procedures

On Wed, 2008-08-20 at 08:50 -0400, Andrew Dunstan wrote:
> 
> Asko Oja wrote:
> > I do get the impression that Tom who would prefer to get all the pl's 
> > out of PostgreSQL and live happily ever after with pure SQL standard.
> >
> >
> 
> I have not seen the slightest evidence of this, and don't believe it for 
> a minute.
>
> I understand some of the frustration you are feeling, but statements 
> like this don't help anything.

Claiming that problems with functions are a "corner case" seems to
indicate that kind of attitude.

OTOH, it may still be, that building really large and complex live
(evolving) databases using postgreSQL is also still a "corner case", so
any bug/limitation that manifests itself when doing DDL under 24/7
database carrying big loads is a "corner case"

> (And yes, I too have recently been bitten nastily by cached plan 
> problems, and want to see them fixed. I rather like Simon's suggestion 
> of a command or function that would clear the plan cache.)

I guess this would be more robust.

Mostly we use _dependencies_ to forbid stuff or to do DROP CASCADE, that
is, to enforce user-visible behaviour.

Cache invalidation seems much lighter and safer operations.

We could even add an option to do a global cache invalidation at the end
of any transaction which does DDL. That would of course need automatic
re-planning the invalidated queries and keeping some intermediate form
of query (with original * expanded to col lists, maybe something else,
basically the same as is currently saved for view's) in order to do so.

-----
Hannu