SQL UCASE函数

该字符串函数显示结构化查询语言中所有字符串字符的大写形式。它将小字符或一组小字符转换为大写字母。

UCASE字符串函数的语法

语法1： 此语法使用SQL表的列名和UCASE函数：

SELECT UCASE(Column_Name) AS Alias_Name FROM Table_Name;

在这个语法中，Column_Name是该列的名称，其值将以大写字母显示。

语法2： 这个语法使用UCASE函数和一组小写字符（字符串）：

SELECT UCASE(String);

Syntax2： 使用UCASE函数与各个小写字符配合的语法：

SELECT UCASE(lower_case_character);

UCASE字符串函数的示例

示例1： 以下SELECT查询将以下字符串的所有字符转换为大写（ucase）：

SELECT UCASE(javatpoint is a good website);

输出:

JAVATPOINT IS A GOOD WEBSITE

示例2： 下面的SELECT查询无法更改以下字符串的字符，因为SQL中的UCASE函数无法更改字符串的符号和整数。

SELECT UCASE(@#$12453@#);

输出：

@#$12453@#

示例3： 以下SELECT查询将小写字母转换为大写字母：

SELECT UCASE( New Delhi IS the Capital OF India);

输出：

NEW DELHI IS THE CAPITAL OF INDIA

示例 4： 以下SELECT查询在输出中以UCASE大小写显示字符’s’：

SELECT UCASE( s );

输出:

S

Example 5: 这个例子使用UCASE函数和SQL表

在这个例子中，我们将创建一个新的表，该表将与UCASE字符串函数一起使用。

在SQL数据库中创建新表的语法如下：

CREATE TABLE table_name
(
1st_Column Data Type (character_size of 1st Column),  
2nd_Column Data Type (character_size of the 2nd column ),  
3rd_Column Data Type (character_size of the 3rd column),  
...  

Nth_Column Data Type (character_size of the Nth column)
);  

以下是创建Faculty_Info表的CREATE语句：

CREATE TABLE Faculty_Info
(
Faculty_ID INT NOT NULL PRIMARY KEY,  
Faculty_First_Name VARCHAR (100),  
Faculty_Last_Name VARCHAR (100),  
Faculty_Dept_Id INT NOT NULL,
Faculty_Address Varchar(120),
Faculty_City Varchar (80),
Faculty_Salary INT 
);

下面的INSERT查询将大学教师的记录插入到 Faculty_Info 表中：

INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary) VALUES (1001, arush, sharma, 4001, aman vihar, delhi, 20000);
INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary) VALUES (1002, bulbul, roy, 4002, nirman vihar, delhi, 38000 );
INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary) VALUES (1004, saurabh, sharma, 4001, sector 128, mumbai, 45000);
INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary) VALUES (1005, shivani, singhania, 4001, vivek vihar, kolkata, 42000);
INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary) VALUES (1006, avinash, sharma, 4002, sarvodya calony, delhi, 28000);
INSERT INTO Faculty_Info (Faculty_ID, Faculty_First_Name, Faculty_Last_Name Faculty_Dept_Id, Faculty_Address, Faculty_City, Faculty_Salary)VALUES (1007, shyam, besas, 4003, krishna nagar, lucknow, 35000);

以下SELECT语句显示上述 Faculty_Info 表中插入的记录：

SELECT * FROM Faculty_Info;

以下SELECT查询使用UCASE函数与上述的Faculty_Info表的Faculty_Last_Name列：

SELECT Faculty_Last_Name, UCASE(Faculty_Last_Name) AS UCASE_LastName FROM Faculty_Info;

这个SQL语句将上表中每个教师的姓氏转换为大写。

输出：

以下SELECT查询使用UCASE函数与上述Faculty_Info表中faculty_Id大于1002的教师的Faculty_First_Name、Faculty_City和Faculty_Address列：

SELECT Faculty_Id, UCASE(Faculty_First_Name), UCASE(Faculty_Address), UCASE(Faculty_City) FROM Faculty_Info WHERE Faculty_Id >1002;

输出：

以下SELECT查询在上面的Faculty_Info表中使用UCASE函数与Faculty_Last_Name和Faculty_Address列，查询工资大于30000的教职员工的相关信息：

SELECT Faculty_Id, UCASE(Faculty_Last_Name), Faculty_Dept_Id, UCASE(Faculty_Address), UCASE(Faculty_Salary) FROM Faculty_Info WHERE Faculty_Salary > 30000;

输出：