How to decrease AUTO_INCREMENT?

Question

MySQL

There are records in the table with A_I `id`
and so there is a big gap between 15000 and 700000
how can AUTO_INCREMENT be returned to the value of 15000, I tried to set it but the value is reset to 700k

Answer 1

Most likely you are using INSERT ON DUPLICATE KEY UPDATE or a similar mechanism that tries to insert records and stumbles. It is he who winds up AUTO_INCREMENT.
To solve it, you need to use a transaction, in which the existence of a duplicate is first checked, and then manipulation is performed.