mysql如何查出右表中符合条件的左表记录？

Question

现在需求是，查询出最近2个月没有操作记录的管理员姓名，比如现在是4月，那么最近两个月都没活动的应就是小明（操作日期以最新的操作日期为判断依据），想问下这样如果用sql写需要怎么写呢？小白一枚，大神勿喷

Answer 1

不确定你的数据库类型，拿mysql写了一下你参考一下

select * from admin where id not in (select distinct admin_id from admin_log where  created_at > date_sub(now(),interval 2 month)

Answer 2

SELECT a.name
FROM admin a
INNER JOIN (
  SELECT admin_id, MAX(created_at) AS latest_created_at
  FROM admin_log
  GROUP BY admin_id
) AS latest_b ON a.id = latest_b.admin_id
WHERE latest_b.latest_created_at < DATE_SUB(NOW(), INTERVAL 2 MONTH)