Manual:User former groups table

Stores the groups the user has once belonged to. The user may still belong these groups. Check user_groups.

Schema summary

 * ufg_user: Key to user_id.
 * ufg_group: Name of the group, which the user was member of.

mysql> describe user_former_groups; +---+--+--+-+-+---+ +---+--+--+-+-+---+ +---+--+--+-+-+---+ 2 rows in set (0.11 sec)
 * Field    | Type             | Null | Key | Default | Extra |
 * ufg_user | int(10) unsigned | NO   | PRI | 0       |       |
 * ufg_group | varbinary(16)   | NO   | PRI |         |       |