Re: tracking commit timestamps

On 25/11/14 16:30, Alvaro Herrera wrote:
> Petr Jelinek wrote:
>> On 25/11/14 16:23, Alvaro Herrera wrote:
>>> Robert Haas wrote:
>
>>>> Maybe 0 should get translated to a NULL return, instead of a bogus timestamp.
>>>
>>> That's one idea --- surely no transaction is going to commit at 00:00:00
>>> on 2000-01-01 anymore.  Yet this is somewhat discomforting.
>>
>> I solved it for xids that are out of range by returning -infinity and then
>> changing that to NULL in sql interface, but no idea how to do that for
>> aborted transactions.
>
> I guess the idea is that we just read the value from the slru and if it
> exactly matches allballs we do the same -infinity return and translation
> to NULL.  (Do we really love this -infinity idea?  If it's just an
> internal API we can use a boolean instead.)
>

As in returning boolean instead of void as "found"? That works for me 
(for the C interface).

--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
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