isValidDSN example

return false;
    }

    /** * Connect to the database. * * @return false|resource */
    public function connect(bool $persistent = false)
    {
        if (empty($this->DSN) && ! $this->isValidDSN()) {
            $this->buildDSN();
        }

        $func = $persistent ? 'oci_pconnect' : 'oci_connect';

        return empty($this->charset)
            ? $func($this->username, $this->password, $this->DSN)
            : $func($this->username, $this->password, $this->DSN, $this->charset);
    }

    /** * Keep or establish the connection if no queries have been sent for * a length of time exceeding the server's idle timeout. * * @return void */