Re: Built-in plugin for logical decoding output

On Tue, Sep 26, 2017 at 2:16 PM, Alvaro Hernandez <aht(at)ongres(dot)com> wrote:

>
>
> On 26/09/17 12:57, Petr Jelinek wrote:
>
>> On 26/09/17 09:26, Alvaro Hernandez wrote:
>>
>>> On 26/09/17 10:03, Craig Ringer wrote:
>>>
>>>> On 26 September 2017 at 14:08, Alvaro Hernandez <aht(at)ongres(dot)com
>>>> <mailto:aht(at)ongres(dot)com>> wrote:
>>>> - If you stick to in-core plugins, then you need to support at
>>>> least three different output formats if you want to support 9.4+:
>>>> test_decoding (and pray it works!), pgoutput, and the "new"
>>>> in-core plugin that was proposed at the beginning of this thread,
>>>> if that would see the light.
>>>>
>>>>
>>>> The only practical way will IMO be to have whatever new plugin it also
>>>> have an out-of-core version maintained for older Pg versions, where it
>>>> can be installed.
>>>>
>>>> But only in-core plugins help for general-purpose solutions.
>>>>
>>>>
>>>> I still don't agree there. If there's enough need/interest/adoption
>>>> you can get cloud vendors on board, they'll feel the customer
>>>> pressure. It's not our job to create that pressure and do their work
>>>> for them.
>>>>
>>> Don't want to get into a loop, but as I said before it's
>>> chicken-and-egg. But nobody is asking core to do their work. As much as
>>> I love it, I think logical decoding is a bit half-baked until there is a
>>> single, quality, in-core plugin, as it discourages its usage, because of
>>> the reasons I stated.
>>>
>>> Well, in that case it's all good as PG10 has that.
>>
>>
> Even though it's not fully documented, I agree this could fulfill this
> gap for 10+ (I assume this plugin will be maintained onwards, at least to
> support logical replication).
>
> 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...

The likelihood is zero if you mean backported into core of earlier versions.

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.

--
Magnus Hagander
Me: https://www.hagander.net/ <http://www.hagander.net/>
Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>