Re: Range Types - typo + NULL string constructor

Excerpts from Robert Haas's message of mié oct 26 13:19:47 -0300 2011:
> On Wed, Oct 26, 2011 at 11:52 AM, Heikki Linnakangas
> <heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:

> > 1. In session A: BEGIN; SELECT * FROM foo WHERE id = 1; COMMIT;
> >   The row has xmin = 123456, and it is cached as committed in the one-item
> > cache by TransactionLogFetch.
> > 2. A lot of time passes. Everything is frozen, and XID wrap-around happens.
> > (Session A is idle but not in a transaction, so it doesn't inhibit
> > freezing.)
> > 3. In session B: BEGIN: INSERT INTO foo (id) VALUES (2); ROLLBACK;
> >   By coincidence, this transaction was assigned XID 123456.
> > 4. In session A: SELECT * FROM foo WHERE id = 2;
> >   The one-item cache still says that 123456 committed, so we return the
> > tuple inserted by the aborted transaction. Oops.
>
> Oh, hmm. That sucks.

Can this be solved by simple application of the Xid epoch?

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Álvaro Herrera <alvherre(at)commandprompt(dot)com>
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