如何在manyToOne关系中插入数据？NestJs

import { Entity, Column, ManyToOne } from 'typeorm';
import { User } from './user.entity';

@Entity()
export class Order {
  // 其他字段...
  
  @ManyToOne(() => User, user => user.orders)
  user: User;
}

import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { User } from './user.entity';

@Injectable()
export class UserService {
  constructor(
    @InjectRepository(User)
    private userRepository: Repository<User>,
  ) {}

  async getUserById(id: number): Promise<User> {
    return this.userRepository.findOne(id);
  }
}

import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { Order } from './order.entity';
import { UserService } from './user.service';

@Injectable()
export class OrderService {
  constructor(
    @InjectRepository(Order)
    private orderRepository: Repository<Order>,
    private userService: UserService,
  ) {}

  async createOrder(userId: number, orderData: any): Promise<Order> {
    const user = await this.userService.getUserById(userId);
    const order = this.orderRepository.create({ ...orderData, user });
    return this.orderRepository.save(order);
  }
}