Re: Built-in plugin for logical decoding output

On 26 September 2017 at 22:14, Magnus Hagander <magnus(at)hagander(dot)net> wrote:

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> On Tue, Sep 26, 2017 at 2:16 PM, Alvaro Hernandez <aht(at)ongres(dot)com> wrote:
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>> But what about earlier versions? Any chance it could be backported
>> down to 9.4? If that would be acceptable, I could probably help/do that...
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> The likelihood is zero if you mean backported into core of earlier
> versions.
>

Right. We don't add features to back branches.

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> If you mean backported as a standalone extension that could be installed
> on a previous version, probably. I'm not sure if it relies on any internals
> not present before that would make it harder, but it would probably at
> least be possible.
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All the pub/sub stuff is new and hooked into syscache etc. So you'd be
doing a bunch of emulation/shims using user catalogs. Not impossible, but
probably irritating and verbose. And you'd have none of the DDL required to
manage it, so you'd need SQL-function equivalents.

I suspect you'd be better off tweaking pglogical to speak the same protocol
as pg10, since the pgoutput protocol is an evolution of pglogical's
protocol. Then using pglogical on older versions.

--
Craig Ringer http://www.2ndQuadrant.com/
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