Discovered some fun things in MySQL today..

Set the variable @id to 0: SET @id = 0;

Update the column id to be id + 1 - this will re-index your id column in one fell swoop. Very nice: UPDATE tblname SET id = (@id := @id + 1);

Set the first value for an auto_increment column: ALTER TABLE tblname AUTO_INCREMENT = 196; (this won’t work if there are rows with a higher value already in the table)

All in all, a few nice bits and pieces for cleaning up your tables.