common\models\Building::getKeyValuePairs PHP Method

    public static function getKeyValuePairs($schoolId)
    {
        $sql = 'SELECT id, name FROM ' . self::tableName() . ' WHERE school_id=:school_id ORDER BY name ASC';
        return Yii::$app->db->createCommand($sql, [':school_id' => $schoolId])->queryAll(\PDO::FETCH_KEY_PAIR);
    }

 public function actionBuildings($id)
 {
     return Building::getKeyValuePairs($id);
 }