MySQL 如何选择电子邮件中@符号之前的所有内容

使用SUBSTRING_INDEX选择电子邮件中@符号之前的所有内容−

select substring_index(yourColumnName,'@',1) from yourTableName;

让我们首先创建一个表−

mysql> create table DemoTable
-> (
-> EmployeeMailId varchar(100)
-> );
Query OK, 0 rows affected (0.52 sec)

使用插入命令向表中插入一些记录−

mysql> insert into DemoTable values('Larry123@gmail.com');
Query OK, 1 row affected (0.16 sec)

mysql> insert into DemoTable values('987Sam@hotmail.com');
Query OK, 1 row affected (0.13 sec)

mysql> insert into DemoTable values('123456David_98@gmail.com');
Query OK, 1 row affected (0.20 sec)

使用select语句显示表中的所有记录−

mysql> select *from DemoTable;

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输出

这将产生以下输出−

+--------------------------+
| EmployeeMailId           |
+--------------------------+
| Larry123@gmail.com       |
| 987Sam@hotmail.com       |
| 123456David_98@gmail.com |
+--------------------------+
3 rows in set (0.00 sec)

这里是查询选择电子邮件中@符号之前的所有内容−

mysql> select substring_index(EmployeeMailId,'@',1) from DemoTable;

输出

这将产生以下输出−

+---------------------------------------+
| substring_index(EmployeeMailId,'@',1) |
+---------------------------------------+
| Larry123                              |
| 987Sam                                |
| 123456David_98                        | 
+---------------------------------------+
3 rows in set (0.00 sec)