0

有谁知道怎么找？我有 3 列

1-身份证

2 - 用户名

3-IP

样本数据为：

+----+-----------+----------------+
| id | username  |    ip          |
+----+-----------+----------------+
|  1 | John      |  127.0.0.1     | 
|  2 | John      |  127.0.0.1     | 
|  3 | John      |  127.0.0.1     | 
|  4 | John      |  127.0.0.1     | 
|  5 | John      |  127.0.0.1     | 
|  6 | John      |  127.0.0.2     | 
|  7 | John      |  127.0.0.2     | 
|  8 | John      |  127.0.0.3     | 
|  9 | John      |  127.0.0.1     | 
| 10 | John      |  127.0.0.1     | 
| 11 | John      |  127.0.0.1     | 
| 12 | Pit       |  127.1.1.1     | 
| 13 | Pit       |  127.1.1.1     | 
| 14 | Pit       |  127.1.1.1     | 
| 15 | Pit       |  127.1.1.1     | 
| 16 | Pit       |  127.1.1.1     | 
| 17 | Pit       |  127.1.1.1     | 
+----+-----------+----------------+

所以我想找到任何值都重复了 ip 在更好的情况下我想找到唯一值所以通过这个查询我可以找到它：

SELECT distinct `username`, `ip` FROM `logs`

现在查询结果是

+----+-----------+----------------+
| id | username  |    ip          |
+----+-----------+----------------+
|  1 | John      |  127.0.0.1     | 
|  7 | John      |  127.0.0.2     | 
|  8 | John      |  127.0.0.3     | 
| 12 | Pit       |  127.1.1.1     | 
+----+-----------+----------------+

这很好，但我真正想要的是什么？我想找到任何用户名有重复的 ip 所以结果必须：

+----+-----------+----------------+
| id | username  |    ip          |
+----+-----------+----------------+
|  1 | John      |  127.0.0.1     | 
|  7 | John      |  127.0.0.2     | 
|  8 | John      |  127.0.0.3     | 
+----+-----------+----------------+

因为那里的坑没有重复的 ip 我怎样才能从结果中删除坑？

4

4 回答 4

1

尝试以下 -

SELECT `logs`.`username`, `logs`.`ip`
FROM (
    SELECT `username`
    FROM `logs`
    GROUP BY `username`
    HAVING COUNT(DISTINCT `ip`) > 1
) AS `dups`
INNER JOIN `logs`
    ON `dups`.`username` = `logs`.`username`
GROUP BY `logs`.`username`, `logs`.`ip`;

更新随着数据集的增长，在用户名和 ip 上添加索引会对该查询的性能产生很大影响 -

CREATE INDEX `IX_username_ip` ON `logs` (`username`, `ip`);
于 2012-04-04T13:34:59.287 回答
0 
SELECT distinct `username`, `ip` 
FROM `logs`
WHERE `username` 
  IN (SELECT `username`
      FROM `logs`
      GROUP BY `username`
      HAVING COUNT(*) >1)
于 2012-04-04T13:36:14.730 回答
0

尝试这个

SELECT l1.username, l1.ip FROM logs l1
INNER JOIN logs l2
    ON l2.username = l1.username
    AND l2.ip != l1.ip
GROUP BY l1.username, l1.ip
于 2012-04-04T13:38:43.820 回答
-1 
   select distinct username,group_concat( distinct ip ) ,count(distinct ip) as cnt from table_name group by username  having cnt>1;
于 2012-04-04T13:38:11.180 回答