How do I change the alias of a column in Typeorm? - sql

Question

I want to change the name of a field with my QueryBuilder in the response body i.e a field called id, I want it to output as staff_id, I am having difficulties with that.
import { getRepository, Like } from 'typeorm';
import { RoomEntity } from '#entity/room.entity';
import { HttpException } from '#exceptions/HttpException';
import { isEmpty } from '#utils/util';
import { Room } from '#/interfaces/room.interface';
class RoomService {
public room = RoomEntity;
public async findQueryRoom(): Promise<Room[]> {
const rooms = await getRepository(this.room)
.createQueryBuilder('room')
.select(['room.id as staff_id', 'room.name'])
.getMany();
return rooms;
}
}
export default RoomService;
In the controller, I have:
import { NextFunction, Request, Response } from 'express';
import { Room } from '#interfaces/room.interface';
import RoomService from '#services/room.service';
class RoomsController {
public roomService = new RoomService();
public getRoomsByQuery = async (req: Request, res: Response, next: NextFunction): Promise<void> => {
try {
const findAllRoomsData: Room[] = await this.roomService.findQueryRoom();
res.status(200).json({ data: findAllRoomsData, message: 'found all' });
} catch (error) {
next(error);
}
};
}
export default RoomsController;
The response I have in my postman does not include the staff_id field, I see
"data": [
{
"name": "Soba"
}
]
How can I solve this problem?

Answer 1

I don't know if you have gotten the solution already, but for those that are facing the same problem using select column alias with TypeORM. I face the same problem some time ago and below was my solution I don't know if it's a convincing solution but it solve my problem.
public async findQueryRoom(): Promise<Room[]> {
const rooms = await getRepository(this.room)
.createQueryBuilder('room')
.select(['room.id AS staff_id', 'room.name AS name'])
.groupBy("room.id")
.getRawMany();
return rooms;
}
Why .groupBy("room.id") when .groupBy("room.id") was absent it keep on selecting each row as many as the total row for example if there are 5 rows in total it will return each row 5 times that is why I introduced .groupBy("room.id") to rid of that.
For 'room.name AS name' if you leave 'room.name' it will return room_name instead of name.