Re: time-delayed standbys

On Fri, Jun 17, 2011 at 11:34 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Thu, Jun 16, 2011 at 10:10 PM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
>>>> According to the above page, one purpose of time-delayed replication is to
>>>> protect against user mistakes on master. But, when an user notices his wrong
>>>> operation on master, what should he do next? The WAL records of his wrong
>>>> operation might have already arrived at the standby, so neither "promote" nor
>>>> "restart" doesn't cancel that wrong operation. Instead, probably he should
>>>> shutdown the standby, investigate the timestamp of XID of the operation
>>>> he'd like to cancel, set recovery_target_time and restart the standby.
>>>> Something like this procedures should be documented? Or, we should
>>>> implement new "promote" mode which finishes a recovery as soon as
>>>> "promote" is requested (i.e., not replay all the available WAL records)?
>>>
>>> I like the idea of a new promote mode;
>>
>> Are you going to implement that mode in this CF? or next one?
>
> I wasn't really planning on it - I thought you might want to take a
> crack at it.  The feature is usable without that, just maybe a bit
> less cool.

Right.

> Certainly, it's too late for any more formal submissions
> to this CF, but I wouldn't mind reviewing a patch if you want to write
> one.

Okay, I add that into my TODO list. But I might not have enough time
to develop that.
So, everyone, please feel free to implement that if you want!

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center