public function addConnection(
        $name,
        $dsn = null,
        array $mapping = null,
        $defaultDatabase = null,
        array $connectOptions = null
    ) {
        $this->configuration[$name] = array(
            'dsn'               => $dsn,
            'connectOptions'    => $connectOptions,
            'defaultDatabase'   => $defaultDatabase,
            'mapping'           => $mapping,
        );
        
        return $this;
    }