MySQL 如何在表中查找所有大写字符串

要在MySQL表中查找所有大写字符串，您需要使用BINARY UPPER()函数。语法如下：

SELECT * FROM yourTableName WHERE yourColumnName = BINARY UPPER(yourColumnName);

为了理解上面的语法，让我们创建一个表。创建表的查询如下所示：

mysql> create table FindUpperCaseDemo
   -> (
   -> Id int,
   -> FirstName varchar(20),
   -> Age int
   -> );
Query OK，0 rows affected (1.04 sec)

使用insert命令在表中插入一些记录。查询如下所示：

mysql> insert into FindUpperCaseDemo values(1,'John',23);
Query OK，1 row affected (0.17 sec)
mysql> insert into FindUpperCaseDemo values(2,'CAROL',21);
Query OK，1 row affected (0.29 sec)
mysql> insert into FindUpperCaseDemo values(3,'JoHN',23);
Query OK，1 row affected (0.11 sec)
mysql> insert into FindUpperCaseDemo values(4,'JOHN',26);
Query OK，1 row affected (0.22 sec)
mysql> insert into FindUpperCaseDemo values(5,'sAM',26);
Query OK，1 row affected (0.18 sec)
mysql> insert into FindUpperCaseDemo values(6,'SAM',28);
Query OK，1 row affected (0.18 sec)
mysql> insert into FindUpperCaseDemo values(7,'MIKE',29);
Query OK，1 row affected (0.17 sec)
mysql> insert into FindUpperCaseDemo values(8,'BOB',20);
Query OK，1 row affected (0.45 sec)
mysql> insert into FindUpperCaseDemo values(9,'LARRY',22);
Query OK，1 row affected (0.39 sec)
mysql> insert into FindUpperCaseDemo values(10,'LARRy',22);
Query OK，1 row affected (0.14 sec)

使用select语句显示表中的所有记录。查询如下所示：

mysql> select * from FindUpperCaseDemo;

以下是输出结果：

+------+-----------+------+
| Id   | FirstName | Age  |
+------+-----------+------+
|    1 | John      |   23 |
|    2 | CAROL     |   21 |
|    3 | JoHN      |   23 |
|    4 | JOHN      |   26 |
|    5 | sAM       |   26 |
|    6 | SAM       |   28 |
|    7 | MIKE      |   29 |
|    8 | BOB       |   20 |
|    9 | LARRY     |   22 |
|   10 | LARRy     |   22 |
+------+-----------+------+
10 rows in set (0.00 sec)

查询所有MySQL表中的大写字符串的查询如下所示：

mysql> select * from FindUpperCaseDemo where FirstName = BINARY UPPER(FirstName);

以下是输出结果：

+------+-----------+------+
| Id   | FirstName | Age  |
+------+-----------+------+
|    2 | CAROL     |   21 |
|    4 | JOHN      |   26 |
|    6 | SAM       |   28 |
|    7 | MIKE      |   29 |
|    8 | BOB       |   20 |
|    9 | LARRY     |   22 |
+------+-----------+------+
6 rows in set (0.09 sec)

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