Secondly, the output of the hash is essentially random. This conflicts with InnoDB's preference to store rows in primary key order. I don't know what kind of l

Secondly, the output of the hash is essentially random. This conflicts with InnoDB's preference to store rows in primary key order. I don't know what kind of lock granularity InnoDB supports but if there are times when you actually want this behavior in order to reduce lock contention.