Re: [HACKERS] make async slave to wait for lsn to be replayed

On 6 March 2018 at 11:24, Dmitry Ivanov  wrote:
>> In PG11, I propose the following command, sticking mostly to Ants'
>> syntax, and allowing to wait for multiple events before it returns. It
>> doesn't hold snapshot and will not get cancelled by Hot Standby.
>>
>> WAIT FOR event [, event ...] options
>>
>> event is
>> LSN value
>> TIMESTAMP value
>>
>> options
>> TIMEOUT delay
>> UNTIL TIMESTAMP timestamp
>> (we have both, so people don't need to do math, they can use whichever
>> they have)
>
>
> I have a (possibly) dumb question: if we have specified several events,
> should WAIT finish if only one of them triggered? It's not immediately
> obvious if we're waiting for ALL of them to trigger, or just one will
> suffice (ANY). IMO the syntax could be extended to something like:
>
> WAIT FOR [ANY | ALL] event [, event ...] options,
>
> with ANY being the default variant.

+1

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