mysql – 选择具有不同区号的重复电话号码的所有行？

我有一个名为contact的表,其中包含以下字段：

+----+-------+--------------+
| id | name  | phone_no     |
+----+-------+--------------+

假设,我在此表中有以下值：

+----+-------+--------------+
| id | name  | phone_no     |
+----+-------+--------------+
| 1  | Alex  | 9907661234   |--1,2 are 
| 2  | Alex  | 09907661234  |--Same contacts but preceding with '0'
| 3  | John  | 9879612363   |--Same contacts but preceding with '91'
| 4  | John  | 919879612363 |-- 91 is (country code)
| 5  | Shawn | 9979867123   |
+----+-------+--------------+

我想找到重复数字的重复联系人数量(这里是前面的数字),0和91是重复的.

我想要以下输出：

+------------+-------------+
| phone_no   |     cn      |
+------------+-------------+
| 9879612363 |           2 |
| 9907661234 |           2 |
+------------+-------------+

最佳答案

假设您的电话号码是10个字符(正如您在问题中所示)并且可选地以某些代码为前缀.然后你可以在MysqL中使用RIGHT(str,len)函数返回指定的最右边的字符数.

查询如下(阅读评论)：

SELECT  RIGHT(`phone_no`,10) as `mobile`,-- selecting last 10 digits
        count(*) as `tatal_count`
FROM `table_name`
GROUP BY `mobile`  -- group by last ten digits
HAVING count(`mobile`) > 1;  -- if you want to select on duplicates

工作范例：

创建表格：

CREATE TABLE IF NOT EXISTS `details` (
  `id` varchar(64) NOT NULL,`name` varchar(64) DEFAULT NULL,`phone` varchar(64) DEFAULT NULL,PRIMARY KEY (`id`)
)

插入查询：

INSERT INTO `details` VALUES 
("1","Alex","9907661234"),("2","09907661234"),("3","John","9879612363"),("4","919879612363"),("5","Shawn","9979867123");

[回答]

MysqL> SELECT  RIGHT(`phone`,->         count(*) as `tatal_count`
    -> FROM `details`
    -> GROUP BY `mobile`
    -> ;
+------------+-------------+
| mobile     | tatal_count |
+------------+-------------+
| 9879612363 |           2 |
| 9907661234 |           2 |
| 9979867123 |           1 |
+------------+-------------+
3 rows in set (0.04 sec)

假设您只想要那些重复的数字(不止一个),那么您可以在MysqL中使用HAVING子句：

MysqL> SELECT  RIGHT(`phone`,->         count(*) as `tatal_count`
    -> FROM `details`
    -> GROUP BY `mobile`
    -> HAVING count(`mobile`) > 1;
+------------+-------------+
| mobile     | tatal_count |
+------------+-------------+
| 9879612363 |           2 |
| 9907661234 |           2 |
+------------+-------------+
2 rows in set (0.00 sec)

我不检查代码是否正确,并假设您在DB中有有效的手机号码