MySQL: Check if the user exists and drop it

Found the answer to this from one of the MySQL forums. We’ll need to use a procedure to delete the user.

User here is “test” and “databaseName” the database name.

SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='ANSI';
USE databaseName ;
DROP PROCEDURE IF EXISTS databaseName.drop_user_if_exists ;
DELIMITER $$
CREATE PROCEDURE databaseName.drop_user_if_exists()
BEGIN
  DECLARE foo BIGINT DEFAULT 0 ;
  SELECT COUNT(*)
  INTO foo
    FROM mysql.user
      WHERE User = 'test' and  Host = 'localhost';
   IF foo > 0 THEN
         DROP USER 'test'@'localhost' ;
  END IF;
END ;$$
DELIMITER ;
CALL databaseName.drop_user_if_exists() ;
DROP PROCEDURE IF EXISTS databaseName.drop_users_if_exists ;
SET SQL_MODE=@OLD_SQL_MODE ;


CREATE USER 'test'@'localhost' IDENTIFIED BY 'a';
GRANT ALL PRIVILEGES  ON databaseName.* TO 'test'@'localhost'
 WITH GRANT OPTION

in terminal do:

sudo mysql -u root -p

enter the password.

select user from mysql.user;

now delete the user 'the_username'

DROP USER the_unername;

replace 'the_username' with the user that you want to delete.

If you mean you want to delete a drop from a table if it exists, you can use the DELETE command, for example:

 DELETE FROM users WHERE user_login = 'foobar'

If no rows match, it's not an error.