Re: Logical subscription / publication lifetimes

Ah, thanks! I should have read the documentation of all the
parameters!

So the portion of data that is covered by "copy_data" is going to
reflect updates and deletes prior to the creation of the slot even if
"publish=insert" (only)?

This makes sense because I can't see how else it could be practically
implemented, but just want to be sure I am understanding. The idea
that there are two phases (copy existing data then replicate
operations) is a big help.

Thanks again,
Andrew

On Fri, Apr 22, 2022 at 09:13:15AM -0700, David G. Johnston wrote:
> On Fri, Apr 22, 2022 at 5:00 AM andrew cooke <andrew(at)acooke(dot)org> wrote:
>
> >
> > If I define a publication at time Tp, then load some data on the
> > publisher, then start a subscription at time Ts, then load some more
> > data on the publisher, does the subscriber get data from Tp or Ts
> > onwards?
> >
> >
> It depends. By default, neither, the publisher is publishing the entire
> contents of the table and the subscriber will do everything necessary to
> replicate those contents in their entirety.
>
> If you specify copy_data = false I'm not sure what you end up with
> initially or after disable. My guess is the subscription defines the first
> transaction it cares about when it connects to the publisher, defaulting to
> the most recent publisher transaction (all older transactions would be
> handled via copy_data = true) but then so long as the slot remains active
> the publisher will place the data into the slot even while the subscriber
> is not active and the subscriber will receive all of it next time it comes
> online/re-enables.
>
> David J.