Mysql 向重复记录添加其他数据

我有一个代码，检查有多少重复代码：

mysql> SELECT code, count(code) as dup from tg_user group by code having dup>1 order by dup;

这将返回：

+------------+-----+
| CCC002     |   5 |
| BAR003     |   6 |
| FIR001     |   6 |
| NJS001     |   6 |
| DEL004     |   6 |
| BRA009     |   7 |
| TSH011     |  11 |
| SHO005     |  19 |
+------------+-----+
432 rows in set (0.08 sec)

表格结构为：

mysql> describe tg_user;
+---------------+--------------+------+-----+---------+----------------+
| Field         | Type         | Null | Key | Default | Extra          |
+---------------+--------------+------+-----+---------+----------------+
| user_id       | int(11)      | NO   | PRI | NULL    | auto_increment |
| user_name     | varchar(30)  | YES  | UNI | NULL    |                |
| email_address | varchar(255) | YES  | UNI | NULL    |                |
| code          | varchar(25)  | YES  |     | NULL    |                |
+---------------+--------------+------+-----+---------+----------------+
32 rows in set (0.00 sec)

为每个重复记录添加电子邮件地址的正确方法是什么，以使其成为列表，例如：

| SHO005     |  19 | name@domai.tld, name@domai.tld...       |
+------------+-----+-----------------------------------------+
432 rows in set (0.08 sec)

---

任何非常受欢迎的建议

添加电子邮件地址的最佳方法就是在select子句中添加该字段，并在group by子句中添加该字段，这将花费最少的时间

比如：-

SELECT code, count(code) as dup ,email_address from tg_user
group by code,email_address having dup>1 order by dup;

---

GROUP\u CONCAT

用逗号连接值。 添加

DISTINCT

以过滤重复项

SELECT code, count(code) as dup, GROUP_CONCAT(DISTINCT email_address)
from tg_user group by code having dup>1 order by dup;