I have a django migration I am trying to apply. It gets made fine (it's small, it's only adding a
At least in PostgreSQL you cannot modify tables (even if it's just adding new columns) while there are active transactions. The easiest workaround for this is usually to:
When restarting your webserver all open transactions will be aborted (assuming you don't have background processes which also have transactions open), so as soon as no transactions are blocking your table, the migration will finish.