Re: Add contrib/pg_logicalsnapinspect

On Thu, Aug 29, 2024 at 3:44 PM Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>
> Yeah that's fair. And now I'm wondering if we need an extra module. I think
> we could "simply" expose 2 new functions in core, thoughts?
>
> > > What do you think? Did you have something else in mind?
> > >
> >
> > On similar lines, we can also provide a function to get the slot's
> > on-disk data.
>
> Yeah, having a way to expose the data from the disk makes fully sense to me.
>
> > IIRC, Bharath had previously proposed a tool to achieve
> > the same. It is fine if we don't want to add that as part of this
> > patch but I mentioned it because by having that we can have a set of
> > functions to view logical decoding data.
>
> That's right. I think this one would be simply enough to expose one or two
> functions in core too (and probably would not need an extra module).

+1 for functions in core unless this extra module
pg_logicalsnapinspect works as a tool to be helpful even when the
server is down.

FWIW, I wrote pg_replslotdata as a tool, not as an extension for
reading on-disk replication slot data to help when the server is down
- https://www.postgresql.org/message-id/flat/CALj2ACW0rV5gWK8A3m6_X62qH%2BVfaq5hznC%3Di0R5Wojt5%2Byhyw%40mail.gmail.com.
When the server is running, pg_get_replication_slots() pretty much
gives the on-disk contents.

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com