Re: Don'st start streaming after creating a slot in pg_receivexlog

On Wed, Jul 29, 2015 at 10:02 AM, Heikki Linnakangas <hlinnaka(at)iki(dot)fi>
wrote:

> On 07/29/2015 10:58 AM, Michael Paquier wrote:
>
>> On Wed, Jul 29, 2015 at 4:51 PM, Heikki Linnakangas <hlinnaka(at)iki(dot)fi>
>> wrote:
>>
>>> On 07/29/2015 10:37 AM, Andres Freund wrote:
>>>
>>>>
>>>> Heikki complained about pg_receivexlog --create-slot starting to stream
>>>> in his talk in St. Petersburg. Saying that that makes it a hard to
>>>> script feature - and I have to agree. Since that option is new to 9.5 we
>>>> can should change that behaviour now if we decide to.
>>>>
>>>
>>> To be clear, I think "pg_receivexlog --create-slot" should only create
>>> the
>>> slot, and exit.
>>>
>>
>> Even if I would like to make pg_recvlogical and pg_receivexlog behave
>> as similarly as possible by having an additional switch --start in
>> pg_receivexlog to control if it starts to stream or not, this ship has
>> already sailed for backward-compatibility's sake... Then let's just
>> create the slot and exit().
>>
>
> Hmm. pg_receivelogical is basically a debugging tool. I don't think anyone
> will have it integrated into production scripts etc. So maybe we could just
> change it.
>
> I'm not sure I understand the proposal though. If you don't specify
> --create-slot, nor --start, what would the program do? Nothing?
>

Maybe we should make --start an optional flag for --create-slot in both
pg_recvlogical and pg_receivexlog?

So that if you didn't use --create-slot or --drop-slot, then it is assumed
that you want to start streaming. And if you're using --create-slot, you
can still start streaming right away, though not by default.

At the moment I find it odd that pg_recvlogical -S myslot doesn't start
streaming and require you to use --start explicitly.

--
*Oleksandr Shulgin*
*Database Engineer*

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