Re: BUG #18988: DROP SUBSCRIPTION locks not-yet-accessed database

On Mon, Aug 18, 2025 at 2:56 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> Looks mostly good. How about slightly changing the comment as in attached?

Your suggestion LGTM, I am making back branch patches. I observed
another behavior change in the test in v13.  The $sdterr is matching
with error details not with the error code, so for v13 i have to
modify the error comparison string as [1] whereas with other versions
it's like [2].  But if we execute this test from psql then I can see
the same error in v13 as well[3].  Not sure why perl is behaving
differently.  Maybe there is a way to change this but I could not
figure it out.  And another difference I have noticed is that in v13 I
had to give complete publisher_connstr that's maybe it's not the
starting server on the default port.  From this I realized that maybe
for other branches where it is working fine with just dbname, we
should also include publisher_connstr as shown [4] just to ensure we
are connecting to the right node, thoughts?

[1]
+like(
+ $stderr,
+ qr/ERROR:  replication slot "regress_sub1" does not exist/,
+ "could not drop replication slot: error message");

[2]

+like(
+ $stderr,
+ qr/ERROR:  could not drop replication slot "regress_sub1" on publisher/,
+ "could not drop replication slot: error message");

[3]
postgres[2045257]=# DROP SUBSCRIPTION regress_sub1;
ERROR:  XX000: could not drop the replication slot "regress_sub1" on publisher
DETAIL:  The error was: ERROR:  replication slot "regress_sub1" does not exist
LOCATION:  DropSubscription, subscriptioncmds.c:1008

[4]

+$publisher_connstr = $node_publisher->connstr . ' dbname=regress_db';
+$node_publisher->safe_psql(
+ 'postgres', qq(
+ CREATE DATABASE regress_db;
+ CREATE SUBSCRIPTION regress_sub1 CONNECTION '$publisher_connstr'
PUBLICATION regress_pub WITH (connect=false);
+));


Attaching only v13 and head patches, once we have a way forward I will
send other patches as well.

--
Regards,
Dilip Kumar
Google