Remove Characters from String in SQL

Here is a function that will remove all characters from string.

CREATE FUNCTION [dbo].[RemoveCharacters](@Str VARCHAR(500))
RETURNS VARCHAR(500)
AS
BEGIN
    WHILE PatIndex('%[^0-9]%', @Str) > 0
    SET @Str = Stuff(@Str, PatIndex('%[^0-9]%', @Str), 1, '')
RETURN @Str 
END
DECLARE @Str VARCHAR(100)
SET @Str = 'A1X2Y3'
SELECT [dbo].RemoveCharacters(@Str)

That’s It.
Enjoy Learning.