mysql> show fields from xf_user_authenticate;
+--------------+------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+------------------+------+-----+---------+-------+
| user_id | int(10) unsigned | NO | PRI | NULL | |
| scheme_class | varchar(75) | NO | | NULL | |
| data | mediumblob | NO | | NULL | |
| remember_key | varbinary(40) | NO | | NULL | |
+--------------+------------------+------+-----+---------+-------+
4 rows in set (0.01 sec)