From PHPBB用户手册

# Table: 'phpbb_acl_roles' 权限角色记录
CREATE TABLE phpbb_acl_roles (
	role_id mediumint(8) UNSIGNED NOT NULL auto_increment, 角色ID, 自增
	role_name varchar(255) DEFAULT '' NOT NULL, 角色名称
	role_description text NOT NULL, 角色描述
	role_type varchar(10) DEFAULT '' NOT NULL, 角色类型
	role_order smallint(4) UNSIGNED DEFAULT '0' NOT NULL,角色显示顺序
	PRIMARY KEY (role_id),
	KEY role_type (role_type),
	KEY role_order (role_order)
) CHARACTER SET `utf8` COLLATE `utf8_bin`;