Re: Time-Delayed Standbys

On 12 December 2013 15:03, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Thu, Dec 12, 2013 at 9:52 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
>>> On 12 December 2013 11:05, Andres Freund <andres(at)2ndquadrant(dot)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.

Don't panic guys! I meant UTC offset only. And yes, it may not be
needed, will check.

--
Simon Riggs http://www.2ndQuadrant.com/
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