Re: tracking commit timestamps

On Tue, Nov 25, 2014 at 9:19 AM, Alvaro Herrera
<alvherre@2ndquadrant.com> wrote:
> Fujii Masao wrote:
>> On Tue, Nov 25, 2014 at 7:58 AM, Alvaro Herrera
>> <alvherre@2ndquadrant.com> wrote:
>> >> And here is v10 which fixes conflicts with Heikki's WAL API changes (no
>> >> changes otherwise).
>> >
>> > After some slight additional changes, here's v11, which I intend to
>> > commit early tomorrow.  The main change is moving the test module from
>> > contrib to src/test/modules.
>>
>> When I specify the XID of the aborted transaction in pg_xact_commit_timestamp(),
>> it always returns 2000-01-01 09:00:00+09. Is this intentional?
>
> Well, when a transaction has not committed, nothing is written so on
> reading we get all zeroes which corresponds to the timestamp you give.
> So yeah, it is intentional.  We could alternatively check pg_clog and
> raise an error if the transaction is not marked either COMMITTED or
> SUBCOMMITTED, but I'm not real sure there's much point.

Maybe 0 should get translated to a NULL return, instead of a bogus timestamp.

-- 
Robert Haas
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