Re: time-delayed standbys

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. 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.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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