Re: Proposal: Generic WAL logical messages

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?

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company