GROUP BY的使用方法

来源:互联网 发布:iphone6sp设置铃声软件 编辑:程序博客网 时间:2024/05/21 07:02

      忙活大半天,终于找出了自己写的SQL语句中的问题。

      错误前:

SELECT  CAST(MONTH(stat_date) AS CHAR) as stat_date ,CAST(COUNT(month(stat_date)) AS CHAR)AS prodcode FROM  tb_ac_syzworderWHERE (SELECT MONTH(stat_date))>(select MONTH(NOW())-4) AND (select MONTH(stat_date))<=(select MONTH(NOW())) GROUP BY stat_date 
      经过老司机的指点,找出了错误原因,其实很简单,之前学sql server时记得老师曾经强调过的。

SELECT  CAST(MONTH(stat_date) AS CHAR) as stat_date ,CAST(COUNT(month(stat_date)) AS CHAR)AS prodcode FROM  tb_ac_syzworderWHERE (SELECT MONTH(stat_date))>(select MONTH(NOW())-4) AND (select MONTH(stat_date))<=(select MONTH(NOW())) GROUP BY  CAST(MONTH(stat_date) AS CHAR) 

  GROUP BY的条件要和SELECT中的一致,不然就会报错的!!!

   长点心吧!!!

原创粉丝点击