select * from ( select university,round(avg(question_cnt),3) as avg_question_cnt, round(avg(answer_cnt),3) as avg_answer_cnt from user_profile GROUP BY university ) as cnt where avg_question_cnt < 5 or avg_answer_cnt < 20 忘記了having, 也可以使用分區(qū)表,在分區(qū)表上做條件刪選