On Wed, Jan 27, 2021 at 2:30 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Tue, Jan 26, 2021 at 9:18 AM japin <japinli@hotmail.com> wrote:
> >
> >
> > When I read the discussion in [1], I found that update subscription's publications
> > is complicated.
> >
> > For example, I have 5 publications in subscription.
> >
> > CREATE SUBSCRIPTION mysub1 CONNECTION 'host=localhost port=5432 dbname=postgres'
> > PUBLICATION mypub1, mypub2, mypub3, mypub4, mypub5;
> >
> > If I want to drop "mypub4", we should use the following command:
> >
> > ALTER SUBSCRIPTION mysub1 SET PUBLICATION mypub1, mypub2, mypub3, mypub5;
> >
> > Also, if I want to add "mypub7" and "mypub8", it will use:
> >
> > ALTER SUBSCRIPTION mysub1 SET PUBLICATION mypub1, mypub2, mypub3, mypub5, mypub7, mypub8;
> >
> > Attached implement ALTER SUBSCRIPTION ... ADD/DROP PUBLICATION ... syntax, for the above
> > two cases, we can use the following:
> >
> > ALTER SUBSCRIPTION mysub1 DROP PUBLICATION mypub4;
> >
> > ALTER SUBSCRIPTION mysub1 DROP PUBLICATION mypub7, mypub8;
> >
> > I think it's more convenient. Any thoughts?
> >
>
> While the new proposed syntax does seem to provide some ease for users
> but it has nothing which we can't do with current syntax. Also, in the
> current syntax, there is an additional provision for refreshing the
> existing publications as well. So, if the user has to change the
> existing subscription such that it has to (a) add new publication(s),
> (b) remove some publication(s), (c) refresh existing publication(s)
> then all can be done in one command whereas with your new proposed
> syntax user has to write three separate commands.
IIUC the initial patch proposed here, it does allow ALTER SUBSCRIPTION
mysub1 ADD/DROP PUBLICATION mypub4 WITH (refresh = true);. Isn't this
option enough to achieve what we can with ALTER SUBSCRIPTION mysub1
SET PUBLICATION mypub1, mypub2 WITH (refresh = true);? Am I missing
something here?
> Having said that, I don't deny the appeal of having separate commands
> for each of (a), (b), and (c).
for (c) i.e. refresh existing publication do we need something like
ALTER SUBSCRIPTION mysub1 REFRESH SUBSCRIPTION or some other syntax
that only refreshes the subscription similar to ALTER SUBSCRIPTION
mysub1 REFRESH PUBLICATION?
With Regards,
Bharath Rupireddy.
EnterpriseDB: http://www.enterprisedb.com
