yii\elasticsearch\Query::scalar PHP Метод

scalar() публичный Метод

The value returned will be the specified field in the first document of the query results.
public scalar ( string $field, Connection $db = null ) : string
$field string name of the attribute to select
$db Connection the database connection used to execute the query. If this parameter is not given, the `elasticsearch` application component will be used.
Результат string the value of the specified attribute in the first record of the query result. Null is returned if the query result is empty or the field does not exist.
    public function scalar($field, $db = null)
    {
        $record = self::one($db);
        if ($record !== false) {
            if ($field === '_id') {
                return $record['_id'];
            } elseif (isset($record['_source'][$field])) {
                return $record['_source'][$field];
            } elseif (isset($record['fields'][$field])) {
                return count($record['fields'][$field]) == 1 ? reset($record['fields'][$field]) : $record['fields'][$field];
            }
        }
        return null;
    }