Re: Check what has been done for a uncommitted prepared transaction

On Thu, May 14, 2020 at 4:05 PM Michael Paquier <michael(at)paquier(dot)xyz> wrote:

> On Thu, May 14, 2020 at 03:38:24PM +0800, Andy Fan wrote:
> > I want to know what happens been done for an uncommitted prepared
> > transaction with pg_waldump, however I can't find it.
> >
> > demo=*# prepare transaction 's';
> > PREPARE TRANSACTION
> > demo=# insert into mm select generate_series(1, 1000);
> > INSERT 0 1000
> >
> > I can get the log for "prepared command" only, but nothing was found for
> > the insert statement. what should I do?
>
> Because in your previous sequence you inserted the data after
> preparing the transaction and they are part of a completely different
> transaction, no?
>

Thanks, actually I don't know how to use prepared transaction and how it
works.
I care about this because there is a long prepared transaction exists in
our customer,
and we want to know what this transaction has done（like any data it
changed).
All the things I know is the data comes from pg_prepared_xact, but it
doesn't help a lot.

Best Regards
Andy Fan