Recovering from a partial recover/migration

I migrated my database with a simple

pg_dump -p <port> -U <user> <database> | psql -p <other port> -U <user> <other database>

and was kindly interrupted by a failing internet connection that killed the process. Now I am stuck with a half-migrated database. What is the easiest way to recover from here without having to delete all data and do it all over again?