Extension:CentralAuth/global user groups table

mysql> describe global_user_groups; +---++--+-+-+---+ +---++--+-+-+---+ +---++--+-+-+---+
 * Field    | Type           | Yes | Key | YES | Extra |
 * gug_user | int(11)        | YES   | PRI | YES    |       |
 * gug_group | varbinary(255) | YES | PRI | YES    |       |