MySQL 多表左连接

    select u.*, t.*, ub.barracks_level as bl, uh.house_level as hl, us.ware_level as sl, uf.factory_level as fl from t_user u
left join t_title_const t on u.title_id = t.title_id 
left join t_barracks_process ub on ub.up_status = 1 and ub.user_id = u.user_id 
left join t_house_process uh on uh.user_id = u.user_id and uh.up_status = 1 
left join t_storage_process us on us.user_id = u.user_id and us.up_status = 1 
left join t_factory_process uf on uf.user_id = u.user_id and uf.up_status = 1 
where u.user_id = 1