[TYPO3-mvc] Repository with external database

[Henk Scholten]

Hello,

I'm pretty new to extbase ans was wondering if this is the right way to 
to call an external database in my repository and put the results in the 
model with extbase:

<?php
namespace Ws\FfPersons\Domain\Repository;

class PersonRepository extends \TYPO3\CMS\Extbase\Persistence\Repository {

	public function initializeObject() {
		$this->conf = 
unserialize($GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf']['ff_persons']);
		$this->db = 
\TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance('TYPO3\\CMS\\Core\\Database\\DatabaseConnection');

		try {
			$this->db->setDatabaseHost($this->conf['hostname']);
			$this->db->setDatabaseUsername($this->conf['username']);
			$this->db->setDatabasePassword($this->conf['password']);
			$this->db->sql_pconnect();
		} catch (\TYPO3\CMS\Fluid\Core\ViewHelper\Exception $exception) {
			throw new 
\TYPO3\CMS\Fluid\Core\ViewHelper\Exception($exception->getMessage());
		}

		try {
			$this->db->sql_select_db($this->conf['database']);
		} catch (\TYPO3\CMS\Fluid\Core\ViewHelper\Exception $exception) {
			throw new 
\TYPO3\CMS\Fluid\Core\ViewHelper\Exception($exception->getMessage());
		}
	}

	/**
	 * findAll
	 *
	 * @return
	 */
	public function findAll() {
		$select = array();
		$select['fields'] = '*';
		$select['table'] = 'persons';
		$select['where'] = '';
		$select['groupby'] = '';
		$select['orderby'] = 'surname';
		$res = $this->db->exec_SELECTquery($select['fields'], 
$select['table'], $select['where'], $select['groupby'], $select['orderby']);

		$persons = array();
		while ($rw = $this->db->sql_fetch_assoc($res)) {
			$personObj = new \Ws\FfPersons\Domain\Model\Person;
			$personObj->setFullname($rw['naam_volledig']);
			$personObj->setNickname($rw['roepnaam']);
			$persons[] = $rw;
		}

		return $persons;
	}

}
?>

I read something about an persistence layer but don't know how to use that.

All suggestions are welcome!

Regards,
Henk