根据同一记录中的某个其他值更新记录值

update record value based on some other value in the same record

我的数据库中有以下 table:

 CREATE TABLE `plans` (
      `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
      `user_id` int(11) DEFAULT NULL,
      `plan` varchar(64) DEFAULT NULL,
      `subscr_id` varchar(64) DEFAULT NULL,
      `last_payment` timestamp NULL DEFAULT NULL,
      `active` tinyint(1) DEFAULT NULL,
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=35 DEFAULT CHARSET=latin1

计划值为1 MONTH3 MONTHSYEAR,分别对应1个月、3个月和12个月。

记录示例:

id----user_id-----plan--------subcr_id-------last_payment--------active

30 |    15     |    1 MONTH  |  A-1   |   2017-05-19 08:22:29   |1

如果 last_payment 发生在一个多月前(如果该记录的计划是 1M),我想遍历每条记录并将 active 更新为 0,超过 3个月前(如果该记录的计划是 3 个月) 和超过 12 个月前(如果该记录的计划是 YEAR)。

虽然我很喜欢table 简单的更新语句,但这个语句需要一些我不知道如何执行的 if 逻辑。你能帮帮我吗?

我认为你应该尝试这样的事情:

UPDATE plans t, (SELECT *  FROM plans) t1
   SET t.active = 0 WHERE date(now()) not between date_add(t1.last_payment,interval t1.plan month)

只需要将plan字段改成整数字段,或者interval(date),应该比做Case scenario简单,但你也可以:

UPDATE `plan` SET `active` = CASE
    WHEN plan = '1 MONTH' THEN CAST(not between date_add(last_payment, interval 1 MONTH) AS SIGNED INTEGER);
    WHEN plan = '3 MONTHS' THEN CAST(not between date_add(last_payment, interval 3 MONTH) AS SIGNED INTEGER);
    WHEN plan = '1 YEAR' THEN CAST(not between date_add(last_payment, interval 1 YEAR) AS SIGNED INTEGER);
    ELSE `1`
    END

大概就是这样,希望对你有帮助

update plans set active = case
when plan = '1 MONTH' and last_payment < now() - interval 1 month then 0
when plan = '3 MONTH' and last_payment < now() - interval 3 month then 0
when plan = 'YEAR' and last_payment < now() - interval 1 year then 0
else 1
end;