Re: Time-Delayed Standbys

On Thu, Dec 12, 2013 at 9:52 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
>> On 12 December 2013 11:05, Andres Freund <andres@2ndquadrant.com> wrote:
>>>> My suggestion would be to add the TZ to the checkpoint record. This
>>>> way all users of WAL can see the TZ of the master and act accordingly.
>>>> I'll do a separate patch for that.
>
>>> Intuitively I'd say that might be useful - but I am not reall sure what
>>> for. And we don't exactly have a great interface for looking at a
>>> checkpoint's data. Maybe add it to the control file instead?
>
>> That's actually what I had in mind, I just phrased it badly in mid-thought.
>
> I don't think you realize what a can of worms that would be.  There's
> no compact representation of "a timezone", unless you are only proposing
> to store the UTC offset; and frankly I'm not particularly seeing the point
> of that.

+1.  I can see the point of storing a timestamp in each checkpoint
record, if we don't already, but time zones should be completely
irrelevant to this feature.  Everything should be reckoned in seconds
since the epoch.

-- 
Robert Haas
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