TypeOrm - 外键插入为Null

最近用nest尝试用typeorm写些数据库操作时，碰到子表保存数据时，外键一直为空。

例如主表:

import { Entity, Column, PrimaryGeneratedColumn, CreateDateColumn, UpdateDateColumn, Generated, OneToMany } from 'typeorm';

import { Post } from './post.entity';

@Entity()

export class User {

  @PrimaryGeneratedColumn()

  id: number;

  @Column()

  userName: string;

  @Column()

  password: string;

  @Column()

  haedImg: string;

  @Column({

    length: 11,

  })

  mobile: string;

  @CreateDateColumn({ type: 'timestamp' })

  createdAt: Date;

  @UpdateDateColumn({ type: 'timestamp' })

  updatedAt: Date;

  @OneToMany(type => Post, post => post.user)

  posts: Post[];

}

子表:

import { Entity, Column, PrimaryGeneratedColumn, CreateDateColumn, UpdateDateColumn, Generated, OneToMany, ManyToOne, JoinColumn } from 'typeorm';

import { User } from './user.entity';

@Entity()

export class Post {

    @PrimaryGeneratedColumn()

    id: number;

    @Column()

    userId: number;  // 一定要定义一遍

    @ManyToOne(type => User, user => user.posts, { nullable: false })

    @JoinColumn({ name: 'userId' })

    user!: User;

    @Column('text')

    img: string;

    @Column('text')

    content: string;

    @Column({ default: 0 })

    shareCount: number;

    @Column({ default: 0 })

    commentCount: number;

    @Column({ default: 0 })

    likeCount: number;

    @Column({ default: 0 })

    collectCount: number;

    @CreateDateColumn({ type: 'timestamp' })

    createdAt: Date;

    @UpdateDateColumn({ type: 'timestamp' })

    updatedAt: Date;

}

原因是userId这个字段也还要再定义一遍，不然就会出现子表插入数据，userId为空的情况