2017-05-22 17:52 GMT-03:00 Dmitry Dolgov <9erthali...@gmail.com>: > Maybe this question was already raised before, but I couldn't find a > discussion. When I'm creating a subscription with `create_slot=false` looks > like it's possible to pass a slot name with invalid characters. In this > particular case both publisher and subscriber were on the same machine: > > =# CREATE SUBSCRIPTION test_sub CONNECTION 'dbname=db host=host > port=port user=user' PUBLICATION test_pub WITH (create_slot=false, > slot_name='test slot'); > NOTICE: 00000: synchronized table states > LOCATION: CreateSubscription, subscriptioncmds.c:443 > CREATE SUBSCRIPTION > Time: 5.887 ms > > The command succeed even if slot_name is invalid. That's because slot_name isn't validated. ReplicationSlotValidateName() should be called in parse_subscription_options() to avoid a pilot error. IMHO we should prevent a future error (use of invalid slot name).
> Of course `test slot` doesn't exist, because I can't create a slot with > incorrect name. And consequently I can't drop this subscription: > > =# DROP SUBSCRIPTION test_sub; > ERROR: XX000: could not drop the replication slot "test slot" on > publisher > DETAIL: The error was: ERROR: replication slot name "test slot" > contains invalid character > HINT: Replication slot names may only contain lower case letters, > numbers, and the underscore character. > LOCATION: DropSubscription, subscriptioncmds.c:947 > Time: 2.615 ms > > Indeed you can drop the subscription. There are two details: (i) subscription should be disabled and (ii) slot name can't be set. bar=# drop subscription sub1; ERROR: could not drop the replication slot "does_not_exist" on publisher DETAIL: The error was: ERROR: replication slot "does_not_exist" does not exist bar=# alter subscription sub1 set (slot_name = NONE); ERROR: cannot set slot_name = NONE for enabled subscription bar=# alter subscription sub1 disable; ALTER SUBSCRIPTION bar=# drop subscription sub1; ERROR: could not drop the replication slot "does_not_exist" on publisher DETAIL: The error was: ERROR: replication slot "does_not_exist" does not exist bar=# alter subscription sub1 set (slot_name = NONE); ALTER SUBSCRIPTION bar=# drop subscription sub1; DROP SUBSCRIPTION Should we add a hint for 'could not drop the replication slot' message? -- Euler Taveira Timbira - http://www.timbira.com.br/ PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento <http://www.timbira.com.br>
