Re: Nested xacts: looking for testers and review

Alvaro Herrera wrote:
> On Fri, May 28, 2004 at 05:43:41PM -0700, Stephan Szabo wrote:
>
> > On Wed, 26 May 2004, Alvaro Herrera wrote:
> >
> > > I have tested it and it passes all regression tests (including ones I
> > > added), plus some more tests I threw at it mainly for concurrency.
> > > Everything behaves as expected. At this time I'd like to have it
> > > reviewed by the critic eye of the committers, and tested by whoever
> > > would be using it.
> >
> > I unfortunately didn't really follow the discussions in the past (sorry :(
> > ), but are the transaction state modifying statements done in a
> > subtransaction supposed to live beyond subtransaction rollback?
>
> Hmm, I suppose not.
>
> I think this applies to all GUC variables, but I wonder if we want to
> save the value of each one at subtransaction start and recover it at
> abort? Things could easily get huge. Maybe only saving the ones that
> are different from the default value, and from the last saved value.

We have an on-commit field in the guc structures to handle
commit/rollback settings. Do we need to extend that to subtransactions?

I don't think you can save off only the defaults in an efficient manner.

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