public function alter($operation)
    {
        return $this->_database->exec(
            'ALTER TABLE ' .
            $this->_database->prepareIdentifier($this->_name) .
            ' ' .
            $operation
        );
    }
public function alter($operation)
    {
        return $this->_database->exec(
            'ALTER TABLE ' .
            $this->_database->prepareIdentifier($this->_name) .
            ' ' .
            $operation
        );
    }
public function alter ( $ operation ) { return $ this -> _database -> exec ( 'ALTER TABLE ' . $ this -> _database -> prepareIdentifier ( $ this -> _name ) . ' ' . $ operation ) ; }
Compose and execute an ALTER TABLE statement

This method simply appends the given operation to an "ALTER TABLE name "
statement and executes it via exec(). Since the operation syntax is often
DBMS-specific, this method is mostly useful for other NADA methods.
@param string $operation SQL fragment
@return mixed Return value of exec()
Compose and execute an ALTER TABLE statement