Re: [COMMITTERS] pgsql: Keep track of transaction commit timestamps

On 04/12/14 12:26, Heikki Linnakangas wrote:
> On 12/04/2014 01:16 PM, Petr Jelinek wrote:
>> On 04/12/14 10:42, Heikki Linnakangas wrote:
>>> On 12/03/2014 04:54 PM, Alvaro Herrera wrote:
>>>> ir commit timestamp directly as they commit,
>>>> or an external transaction c
>>>
>>> Sorry, I'm late to the party, but here's some random comments on this
>>> after a quick review:
>>>
>>> * The whole concept of a node ID seems to be undocumented, and unused.
>>> No-one calls CommitTsSetDefaultNodeId(). The whole SET_TS record type is
>>> dead code too, when a non-default node_id is not set. Please remove, or
>>> explain how all that's supposed to work.
>>
>> That's API meant to be used by extensions, maybe it would be preferable
>> if there was SQL API exposed also?
>>
>> (It might also make more sense once replication identifiers are
>> submitted.)
>
> Maybe. Hard to tell without any documentation or comments on how it's
> supposed to work. In unacceptable in its current state.
>
> I would prefer to remove it now, and add it back later together with the
> code that actually uses it. I don't like having unused internal
> functions and APIs sitting the source tree in the hope that someone will
> find them useful in the future. It's more likely that it will bitrot, or
> not actually work as intended, when someone later tries to use it.

The thing is I already have extension for 9.4 where I would use this API
for conflict detection if it was available so it's not about hoping for
somebody to find it useful. There was discussion about this during the
review process because the objection was raised already then.

>
> What would the SQL API look like, and what would it be used for?
>

It would probably mirror the C one, from my POV it's not needed but
maybe some replication solution would prefer to use this without having
to write C components...

--
Petr Jelinek http://www.2ndQuadrant.com/
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