Citation :
For those that are looking to "reset" the auto_increment, say on a list that has had a few deletions and you want to renumber everything, you can do the following.
DROP the field you are auto_incrementing.
ALTER the table to ADD the field again with the same attributes.
You will notice that all existing rows are renumbered and the next auto_increment number will be equal to the row count plus 1.
(Keep in mind that DROPping that column will remove all existing data, so if you have exterior resources that rely on that data, or the numbers that are already there, you may break the link. Also, as with any major structure change, it's a good idea to backup your table BEFORE you make the change.)
http://dev.mysql.com/doc/mysql/en/ [...] html#c2860
|