FHC-Core/application/models/person/Benutzer_model.php

<?php
class Benutzer_model extends DB_Model
{

	/**
	 * Constructor
	 */
	public function __construct()
	{
		parent::__construct();
		$this->dbTable = 'public.tbl_benutzer';
		$this->pk = array('uid');
		$this->hasSequence = false;
	}

	public function getFromPersonId($person_id)
	{
		return $this->loadWhere(array('person_id' => $person_id, 'aktiv' => true));
	}

	/**
	 *
	 */
	public function getActiveUserByPersonIdAndOrganisationUnit($person_id, $oe_kurzbz)
	{
		$sql = 'SELECT b.uid
				  FROM public.tbl_benutzer b
				  JOIN public.tbl_prestudent ps USING (person_id)
				  JOIN public.tbl_studiengang sg USING (studiengang_kz)
				 WHERE ps.person_id = ?
				   AND sg.oe_kurzbz = ?
				   AND b.aktiv = TRUE';

		return $this->execQuery($sql, array($person_id, $oe_kurzbz));
	}
}