Re: Remove xmin and cmin from frozen tuples

On Fri, Sep 02, 2005 at 05:18:09PM -0400, Tom Lane wrote:
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > Updated TODO:
>
> > o Allow COPY on a newly-created table to skip WAL logging
>
> > On crash recovery, the table involved in the COPY would
> > have its heap and index files truncated. One issue is
> > that no other backend should be able to add to the table
> > at the same time, which is something that is currently
> > allowed.
>
> This is simply wrong. (1) a table created in the current transaction
> isn't visible to anyone else, (2) the correct rollback state is for
> it not to be there, rather than be there and empty.

As a related note:

I remember somebody mentioned some time ago that if you create a table
and then crash before ending the transaction, the tuple in pg_class is
no longer valid, but the file remains. I think this will be a much
worse problem if we allow a table that's being COPY'ed to remain after a
crash.

--
Alvaro Herrera -- Valdivia, Chile Architect, www.EnterpriseDB.com
Oh, oh, las chicas galacianas, lo harán por las perlas,
¡Y las de Arrakis por el agua! Pero si buscas damas
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