Hello. I think I may have found a bug in the CREATE USER MAPPING / DROP SERVER handling.
It is possible to create a user mapping on a server and drop said server in two concurrent transactions, and have both succeed. This results in an orphan row in the pg_user_mapping table. I would expect one of those transactions to fail. This is more easily explained with the following example: CREATE extension postgres_fdw; CREATE server pg_server FOREIGN DATA WRAPPER postgres_fdw -- SESSION 1 BEGIN; CREATE USER MAPPING FOR postgres SERVER pg_server OPTIONS (user 'user'); -- SESSION 2 BEGIN; DROP SERVER pg_server; -- SESSION 1 COMMIT; -- SESSION 2 COMMIT; select umserver, s.oid from pg_user_mapping left join pg_foreign_server s on s.oid = pg_user_mapping.umserver; ┌──────────┬─────┐ │ umserver │ oid │ ├──────────┼─────┤ │62172 │ ¤ │ └──────────┴─────┘ -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
