mysql - LEFT JOINs with multiple tables -

i have following tables:

table users - primary key (user_id) +---------+----------+-----------+ | user_id | username | realname  | +---------+----------+-----------+ |       1 | peterpan | peter pan | |       2 | bobfred  | bod fred  | |       3 | sallybe  | sally  | |       6 | petersep | peter sep | +---------+----------+-----------+  table users_groups - primary key (user_id, group_id) +---------+----------+ | user_id | group_id | +---------+----------+ | 1       | 1        | | 1       | 2        | | 2       | 1        | | 2       | 2        | | 3       | 6        | | 3       | 9        | | 6       | 6        | | 6       | 9        | +---------+----------+  table game - primary key (id) +----+-------+ | id | game  | +----+-------+ | 1  | game1 | | 2  | game2 | | 6  | game6 | | 9  | game9 | +----+-------+  table groups - primary key(group_id) +----------+--------------+---------------+ | group_id | group_name   | group_desc    | +----------+--------------+---------------+ | 1        | groupname1   | description1  | | 2        | groupname2   | description2  | +----------+--------------+---------------+  table group_game - primary key(group_id, game_id) +----------+----------+ | group_id | game_id  | +----------+----------+ | 1        | 1        | | 1        | 2        | | 2        | 6        | | 2        | 9        | +----------+----------+ 

i want display (like group list):

+----+------------+--------------+---------------------+--------------+ | id | group name | group desc   | group members       | group games  | +----+------------+--------------+---------------------+--------------+ |  1 | groupname1 | description1 | peter pan, bob fred | game1, game2 | |  2 | groupname2 | description2 | sally be, peter sep | game6, game9 | +----+------------+--------------+---------------------+--------------+ 

now have query gives me no rows (no error, 0 rows):

select     g.group_name,     g.group_id,     g.group_desc,     group_concat(distinct ga.game separator ', ') games,     group_concat(distinct u.realname separator ', ') users groups g left join users_groups ug1     on g.group_id=ug1.group_id left join users u     on ug1.user_id=u.user_id left join group_game gg    on g.group_id=gg.group_id left join game ga    on gg.game_id=ga.id group g.group_name 

how can solve problem or how can write query?

i want show group list information (like group information, users of groups, games of group).