public function purge()
{
$this->dbHandler->beginTransaction();
$query = $this->dbHandler->createDeleteQuery();
$tables = ['ezsearch_object_word_link', 'ezsearch_return_count', 'ezsearch_search_phrase', 'ezsearch_word'];
foreach ($tables as $tbl) {
$query->deleteFrom($tbl);
$stmt = $query->prepare();
$stmt->execute();
}
$this->dbHandler->commit();
}