Re: Proposal: Generic WAL logical messages

On 29 January 2016 at 21:11, Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru>
wrote:

> Hi, Petr!
>
> On Sat, Jan 23, 2016 at 1:22 AM, Petr Jelinek <petr(at)2ndquadrant(dot)com>
> wrote:
>
>> here is updated version of this patch, calling the messages logical
>> (decoding) messages consistently everywhere and removing any connection to
>> standby messages. Moving this to it's own module gave me place to write
>> some brief explanation about this so the code documentation has hopefully
>> improved as well.
>>
>> The functionality itself didn't change.
>
>
> I'd like to mention that there is my upcoming patch which is named generic
> WAL records.
> *http://www.postgresql.org/message-id/CAPpHfdsXwZmojm6Dx+TJnpYk27kT4o7Ri6X_4OSWcByu1Rm+VA@mail.gmail.com
> <http://www.postgresql.org/message-id/CAPpHfdsXwZmojm6Dx+TJnpYk27kT4o7Ri6X_4OSWcByu1Rm+VA@mail.gmail.com>*
> But it has to be distinct feature from your generic WAL logical messages.
> Theoretically, we could have generic messages with arbitrary content and
> both having custom WAL reply function and being decoded by output plugin.
> But custom WAL reply function would let extension bug break recovery,
> archiving and physical replication. And that doesn't seem to be acceptable.
> This is why we have to develop these as separate features.
>
> Should we think more about naming? Does two kinds of generic records
> confuse people?
>

Logical messages

Generic WAL records

Seems like I can tell them apart. Worth checking, but I think we're OK.

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