MySQL 如何在MySQL字符串中匹配下划线

要在MySQL字符串中匹配下划线，可以使用以下语法 –

select *from yourTableName where yourColumnName LIKE '%\_%';

首先让我们创建一个表 –

mysql> create table DemoTable
(
   ClientId varchar(200)
);
Query OK, 0 rows affected (0.79 sec)

使用插入命令在表中插入一些记录 –

mysql> insert into DemoTable values('CLI_101');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable values('CLI1110');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable values('_CLI102');
Query OK, 1 row affected (0.16 sec)
mysql> insert into DemoTable values('CLI103_');
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable values('CLI1111');
Query OK, 1 row affected (0.16 sec)

以下是使用select语句从表中显示所有记录的查询 –

mysql> select *from DemoTable;

这将产生以下输出 –

+----------+
| ClientId |
+----------+
| CLI_101  |
| CLI1110  |
| _CLI102  |
| CLI103_  |
| CLI1111  |
+----------+
5 rows in set (0.00 sec)

这是使用LIKE匹配字符串中下划线的查询 –

mysql> select *from DemoTable where ClientId LIKE '%\_%';

这将产生以下输出，显示带有下划线的字符串 –

+----------+
| ClientId |
+----------+
| CLI_101  |
| _CLI102  |
| CLI103_  |
+----------+
3 rows in set (0.00 sec)

您可以使用以下替代查询 –

mysql> select *from DemoTable where ClientId REGEXP '_';

这将产生以下输出 –

+----------+
| ClientId |
+----------+
| CLI_101  |
| _CLI102  |
| CLI103_  |
+----------+
3 rows in set (0.00 sec)

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