CASE WHEN用法

问题:假如说这个条件有一条数据不满足,那么那条数据就不会读出来,,那么,我怎么才能把它读出并且赋值为空呢

方法:

 SELECT
     `s`.*, (
         CASE
         WHEN `a`.`status` > 1 THEN
             SUM(a.total_number)
         WHEN `a`.`status` <= 1 THEN
             NULL
         END
     ) AS sales
 FROM
     `ce_order` `a`
 INNER JOIN (
     SELECT
         `s`.*, b.company_name AS bloc_name
     FROM
         `ce_store` `s`
     INNER JOIN `ce_bloc` `b` ON `s`.`bid` = `b`.`id`
 ) s ON `a`.`uid` = `s`.`id`
 GROUP BY
     s.id

直接拷贝CASE 那段到控制器里就可以了

结果: