public function updateSearchIndex()
{
// update search index
$c = new Criteria();
$c->add(SearchIndexPeer::QUESTION_ID, $this->getId());
SearchIndexPeer::doDelete($c);
foreach ($this->getWords() as $word => $weight) {
$index = new SearchIndex();
$index->setQuestionId($this->getId());
$index->setWord($word);
$index->setWeight($weight);
$index->save();
}
}