UPPER

Description

The UPPER function is used to convert all lowercase letters in the input string (str) to uppercase letters and return the converted string.

Syntax

UPPER(str)

Parameters

• str (string): The string that needs to be converted to uppercase.

Return Result

Returns a string where all lowercase letters have been converted to uppercase letters.

Example

1. Convert a simple string:

SELECT UPPER('hello world');
-- Output result: HELLO WORLD

2. Convert strings containing numbers and special characters:

SELECT UPPER('Hello123!@#');
-- Output result: HELLO123!@#

3. Convert a string that is already in uppercase:

SELECT UPPER('HELLOWORLD');
-- Output result: HELLOWORLD

4. Use the UPPER function in queries to process column data:

SELECT UPPER(column_name) FROM table_name;

5. Use in combination with other string functions:

SELECT CONCAT(UPPER(first_name), UPPER(last_name)) AS full_name
FROM users;
-- Assuming the users table contains the first_name and last_name columns, this query will return a column named full_name, which contains the result of converting the user's first name and last name to uppercase.

Notes

• The UPPER function only applies to English letters contained in the input string. For other languages or special characters, the conversion effect may not meet expectations.
• When using the UPPER function, please ensure that the input string is in the correct format. If the input string is not valid text, the function may not work properly.