In SQL Server, you can convert any uppercase string to lowercase by using the LOWER() function.

Simply provide the string as an argument when you call the function, and it will be returned in lowercase form.

Syntax

Here’s the official syntax:

LOWER ( character_expression )

Where character_expression is an expression of character or binary data. This can be a constant, variable, or column. It must be of a data type that is implicitly convertible to varchar. If not, you can use the CAST() function to convert it.

Example 1 – Basic Usage

Here’s an example of LOWER() in action:

SELECT LOWER('POSITIVITY');

Result:

positivity

And we get the same result even if the original string already contains lowercase characters:

SELECT LOWER('Positivity');

Result:

positivity

Example 2 – Database Example

Here’s an example that returns data from a database and converts it to lowercase:

USE Music;
SELECT TOP 5
    AlbumName AS Original, 
    LOWER(AlbumName) AS Lowercase
FROM Albums;

Result:

Original                Lowercase             
----------------------  ----------------------
Powerslave              powerslave            
Powerage                powerage              
Singing Down the Lane   singing down the lane 
Ziltoid the Omniscient  ziltoid the omniscient
Casualties of Cool      casualties of cool    

You can also use UPPER() in the same way to convert a string expression to uppercase.