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: