Re: logical streaming of xacts via test_decoding is broken

On Tue, Nov 10, 2020 at 8:14 AM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Mon, Nov 9, 2020 at 6:00 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> >
> > On Mon, Nov 9, 2020 at 5:37 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> > >
> > > On Mon, Nov 9, 2020 at 4:21 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> > >
> > > The bigger question is do we want to give users an option
> > > > for skip_empty_streams similar to skip_empty_xacts? I would again
> > > > prefer to give a separate option to the user as well. What do you
> > > > think?
> > >
> > > Yeah, I think giving an option would be better.
> >
> > I think we should also think about the combinations of the
> > skip_empty_xacts and skip_empty_streams. For example, if the user
> > passes the skip_empty_xacts to false and skip_empty_streams to true
> > then what should be the behavior, if the complete transaction
> > option1: It should not print any stream_start/stream_stop and just
> > print commit stream because skip_empty_xacts is false and
> > skip_empty_streams is true.
> > option2: It should print the stream_start message for the very first
> > stream because it is the first stream if the txn and skip_empty_xacts
> > is false so print it and later it will print-stream commit.
> > option3: Or for the first stream we first put the BEGIN message i.e
> > stream begin
> > stream start
> > stream stop
> > stream commit
> > option4: the user should not be allowed to pass skip_empty_xacts =
> > false with skip_empty_streams to true. Because if the streaming mode
> > is on then we can not print the xact without printing streams.
> >
> > What is your opinion on this?
> >
>
> I would prefer option-4 and in addition to that we can ensure that if
> skip_empty_xacts = true then by default skip_empty_streams is also
> true.

But then it will behave as a single option only, right? because if
1. skip_empty_xacts = true, then we set skip_empty_streams = true
2. skip_empty_xacts = false then skip_empty_streams can not be set to true

So as per the state machine either both will be true or both will be
false, Am I missing something?

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com