I just upgraded to 2.1 with the usual procedure (pip install -U + indico db upgrade) without stopping the Indico service. I never had problem but this time during DB upgrade I got the following error during
Running upgrade c820455976ba -> 813ea74ce8dc, Add AttachmentFolder.is_hidden step:
sqlalchemy.exc.OperationalError: (psycopg2.extensions.TransactionRollbackError) deadlock detected
DETAIL: Process 13182 waits for AccessExclusiveLock on relation 78502 of database 77071; blocked by process 13099.
Process 13099 waits for AccessShareLock on relation 78947 of database 77071; blocked by process 13182.
HINT: See server log for query details.
[SQL: “ALTER TABLE attachments.folders ADD COLUMN is_hidden BOOLEAN DEFAULT ‘false’ NOT NULL”] (Background on this error at: http://sqlalche.me/e/e3q8)
I re-run indico db upgrade successfully after the error. Do I need to worry about something or was it just a transient error with everything remaining to be done fixed during the second run of the DB upgrade?