Question

We are trying to implement the following case. We have a invoice table and there is a column which has email address. We want to somehow generate a unique int value from this email address and store that in a separate column. This will be used as a FK and indexed. So what I am looking for is an algorithm for generating ints from strings (please note that the email string should always output the same int so each email address as a unique int representation). We can use a bigint as well

Answer 1

Simplest solution is to put the email address into its own table along with an identity/auto_increment type column. Then you can simply carry around that identify field (a standard int), and you don’t run into any issues with potential hash collisions, and no hashing overhead.