On Thu, Jan 18, 2024 at 12:55 PM Masahiko Sawada <sawada.m...@gmail.com> wrote: > ... > > Although we can improve it to handle this case too, I'm not sure it's > a bug. The doc says[1]: > > Specifies whether the subscription should be automatically disabled if > any errors are detected by subscription workers during data > replication from the publisher. > > When an apply worker is trying to establish a connection, it's not > replicating data from the publisher. > > Regards, > > [1] > https://www.postgresql.org/docs/devel/sql-createsubscription.html#SQL-CREATESUBSCRIPTION-PARAMS-WITH-DISABLE-ON-ERROR > > -- > Masahiko Sawada > Amazon Web Services: https://aws.amazon.com
Yeah, I had also seen that wording of those docs. And I agree it leaves open some room for doubts because strictly from that wording it can be interpreted that establishing the connection is not actually "data replication from the publisher" in which case maybe there is no bug. OTOH, it was not clear to me if that precise wording was the intention or not. It could have been written as "Specifies whether the subscription should be automatically disabled if any errors are detected by subscription workers." which would mean the same thing 99% of the time except that would mean that the current behaviour is a bug. I tried looking at the original thread where this feature was born [1] but it is still unclear to me if 'disable_on_error' was meant for every kind of error or only data replication errors. Indeed. even the commit message [2] seems to have an each-way bet: * It talks about errors applying changes --- "Logical replication apply workers for a subscription can easily get stuck in an infinite loop of attempting to apply a change..." * But, it also says it covers any errors --- "When true, both the tablesync worker and apply worker catch any errors thrown..." ~ Maybe we should be asking ourselves how a user intuitively expects this option to behave. IMO the answer is right there in the option name - the subscription says 'disable_on_error' and I got an error, so I expected the subscription to be disabled. To wriggle out of it by saying "Ah, but we did not mean _those_ kinds of errors" doesn't quite seem genuine to me. ====== [1] https://www.postgresql.org/message-id/flat/CAA4eK1KsaVgkO%3DRbjj0bcXZTpeV1QVm0TGkdxZiH73MHfxf6oQ%40mail.gmail.com#d4a0db154fbeca356a494c50ac877ff1 [2] https://github.com/postgres/postgres/commit/705e20f8550c0e8e47c0b6b20b5f5ffd6ffd9e33 Kind Regards, Peter Smith. Fujitsu Australia
