Userdb:groups

CREATE TABLE `groups` (

 `group_id` int(11) NOT NULL AUTO_INCREMENT,
 `group_name` varchar(128) NOT NULL,
 `description` varchar(512) DEFAULT NULL,
 `created_by` int(11) NOT NULL,
 `create_time` datetime NOT NULL,
 `last_change_time` datetime DEFAULT NULL,
 PRIMARY KEY (`group_id`),
 UNIQUE KEY `group_name` (`group_name`),
 KEY `created_by` (`created_by`)

)