MySQL in a Nutshell, 2nd Edition

Name

mysql_change_user()

Synopsis

int mysql_change_user(user, password[, database, connection])

This function can be used to change the username for a MySQL connection. The new username is given as the first argument and the password for that user as the second. A different database from the one in use may be given as a third argument. You can change the user information for a different MySQL connection by specifying it as the fourth argument. If the function is successful, it returns true; if it’s unsuccessful, it returns false. This function is no longer available as of version 4 of PHP. Instead, you should establish a new connection with a different user by using the mysql_connect() function.