求助"查询1个月未登录的用户人数"的语句该怎么写
表名是loglist, 每行记录一个用户一次的登录信息;
能用的字段是: Account(帐号名), ConnectTime(登录时间);
+--------------------+---------------------+------+-----+---------------------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+---------------------+------+-----+---------------------+----------------+
| Account | varchar(16) | NO | MUL | | |
| ConnectTime | datetime | NO | MUL | 0000-00-00 00:00:00 | |
+--------------------+---------------------+------+-----+---------------------+----------------+
数据需求是: 查询1个月未登录的用户人数;
实在写不出来 , 请求各位高手帮我一下, 非常非常感谢;
------解决方案--------------------
可能这个会更好理解一些:
SQL code
mysql> SELECT COUNT(*)
-> FROM
-> (
-> SELECT Account, MAX(ConnectTime) AS Ti
-> FROM loglist
-> GROUP BY Account
-> ) AS T
-> WHERE Ti < (NOW() + INTERVAL -1 MONTH);
+----------+
| COUNT(*) |
+----------+
| 2 |
+----------+
1 row in set (0.00 sec)