SQL 聚合函数---是这样用的 不要再迷糊

下面这才是正确的聚合统计用法,统计出相同的手机号,的订单,不需要的列不要搜索

SELECT top_task_receiver FROM top_task GROUP BY top_task_receiver HAVING COUNT(top_task_id) > 1

 

下面这样用是错的,因为top_task_id没有包含在group by 中

SELECT top_task_id,top_task_receiver FROM top_task GROUP BY top_task_receiver HAVING COUNT(top_task_id) > 1