make an ID in a mysql table auto_increment (after the fact)

Question

I acquired a database from another developer. He didn\'t use auto_incrementers on any tables. They all have primary key ID\'s, but he did all the incrementing manually, in

Answer 1

As long as you have unique integers (or some unique value) in the current PK, you could create a new table, and insert into it with IDENTITY INSERT ON. Then drop the old table, and rename the new table.

Don't forget to recreate any indexes.