public static function getTeachersCountGroupByArea() { $result = Yii::$app->db->createCommand('SELECT count(t.id) as count,train.district FROM ' . self::tableName() . ' t LEFT JOIN ' . TrainTeachers::tableName() . ' tt ON t.id = tt.teachers_id LEFT JOIN ' . Train::tableName() . ' train ON tt.train_id = train.id WHERE train.district is not null group by train.district')->queryAll(); return $result; }