In first MySQL statement, you will remove the auto-increment from the column and in second statement, you will again declare the field as autoincrement. This way the auto increment counter will reset ...

For InnoDB you cannot set the auto_increment value lower or equal to the highest current index. This is the sample example: Here you can see that I am deleting records from table user_invites having 5 ...

However, since the auto-increment has to be (part of) the primary key in MySQL, you won't be able to distinguish those duplicate records which need to be updated once you define an auto-increment. One ...