SELECT t1.id,t1.group_name,t1.avatar,group_des,COUNT(*) AS `count`
FROM t_group t1 LEFT JOIN t_grouping t2 ON t1.`id` = t2.`group_id`
WHERE creat_people_id = 1
GROUP BY t1.`id`
ORDER BY t1.`id` ASC
应该查出来的效果是软件工程七班count=0
t_group表 里面存储着每个组的信息
t_grouping表 里面存储每个组对应的组员身份id