The Importance of Database Level Locks

The job of a database, if you acquire a lock using a database feature, such as Postgres, select, start or select ID from table. That's how you acquire an exclusive lock in Postgres. If you do that, the database is acquiring the lock for you and its responsibility. A good database system will release the lock the moment you end the transaction. However, there is this concept of logical locks or application level locks and those are nasty. You're maintaining your own idea of locks.