static function getParent($id) { if (!Validator::number($id, 1)) { return null; } $context = Model_Context::getInstance(); $pool = new DBModel(); $pool->reset('Categories'); $blogid = intval($context->getProperty('blog.id')); $pool->setQualifier('blogid', 'equals', $blogid); $pool->setQualifier('id', 'equals', $id); return $pool->getCell('parent'); }