public function getDependencies()
{
$dependencies = $this->getData('dependencies');
if (empty($dependencies)) {
$select = new Sql\Select();
$select->from(array('dtd' => 'document_type_dependency'))->columns(array('children_id'))->where->equalTo('parent_id', $this->getId());
$rows = $this->fetchAll($select);
$result = array();
foreach ($rows as $row) {
$result[] = $row['children_id'];
}
$this->setData('dependencies', $result);
}
return $this->getData('dependencies');
}