How to free User ID after him delete? Is meant him number.

Are you inferring that you would want to use the same member ID again?

If so generally it is not advised as there may be traces of data left that are linked to it. The auto number increment system in MySql sees to most of the management: https://dev.mysql.com/doc/refman/5.0/en/example-auto-increment.html

The members table uses an auto-increment value for the ID number, as Rugger noted, and you cannot "reuse" a deleted ID.

ok, Thank you!