Re: Prepared statements fail after schema changes with surprising error

On Wed, Jan 23, 2013 at 8:10 AM, Dimitri Fontaine
<dimitri@2ndquadrant.fr> wrote:
> Really, live DDL is not that frequent, and when you do that, you want
> transparent replanning. I can't see any use case where it's important to
> be able to run DDL in a live application yet continue to operate with
> the old (and in cases wrong) plans.

I agree with that, but I think Tom's concern is more with the cost of
too-frequent re-planning.  The most obvious case in which DDL might be
frequent enough to cause an issue here is if there is heavy use of
temporary objects - sessions might be rapidly creating and dropping
objects in their own schemas.  It would be unfortunate if that forced
continual replanning of queries in other sessions.  I think there
could be other cases where this is an issue as well, but the
temp-object case is probably the one that's most likely to matter in
practice.

-- 
Robert Haas
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