How to remove special characters by mysql custom function.

Mysql custom fucntion is a very prety and intresting concept. In this posts i want to create one custom mysql function for remove special characters from table field value. this function through you can also remove special characters from string in mysql. in following sql query fire in your mysql or mssql database and check how it works. So, lets create function and how to use in select statement in sql query.

Create removeSpacialChar function:

CREATE FUNCTION `removeSpacialChar`(`in_str` varchar(4096)) RETURNS varchar(4096) CHARSET utf8 
BEGIN
      DECLARE out_str VARCHAR(4096) DEFAULT ''; 
      DECLARE c VARCHAR(4096) DEFAULT ''; 
      DECLARE pointer INT DEFAULT 1; 
 
      IF ISNULL(in_str) THEN
            RETURN NULL; 
      ELSE
            WHILE pointer <= LENGTH(in_str) DO 
 
                  SET c = MID(in_str, pointer, 1); 
 
                  IF (ASCII(c) >= 48 AND ASCII(c) <= 57) OR (ASCII(c) >= 65 AND ASCII(c) <= 90) OR (ASCII(c) >= 97 AND ASCII(c) <= 122) THEN
                      SET out_str = CONCAT(out_str, c); 
                  ELSE
                      SET out_str = CONCAT(out_str, ' ');   
                  END IF; 
 
                  SET pointer = pointer + 1; 
            END WHILE; 
      END IF; 
 
      RETURN out_str; 
END

Use With Select Query:

SELECT removeSpacialChar(users.name) FROM `users`