Javascript 找不到别名。也许你忘了参加

在我的nectjs项目中，我使用的是TypeORM，我有两个实体用户和帖子， 我想在他们之间建立一种关系

user.entity.ts post.entity.ts 所以我想加入这些表，并通过特定用户的标题获取帖子

const PostObject = await createQueryBuilder("post")
      .leftJoinAndSelect(
        "post.user",
        "user",
        "post.title = :title",
        { title: "title1" }
      )
      .where("user.id = :id", { id: id })
      .getOne();

但是，当我运行项目并执行此函数时，会出现以下错误：

Error: "post" alias was not found. Maybe you forget to join it?

---

您必须首先注入

存储库

：

constructor(
  @InjectRepository(Post) private readonly postRepository: Repository<Post>
) {
}

Error: "post" alias was not found. Maybe you forget to join it?

constructor(
  @InjectRepository(Post) private readonly postRepository: Repository<Post>
) {
}

this.postRepository.createQueryBuilder('post')
// ^^^^^^^^^^^^^^^^
   .leftJoinAndSelect(
     'post.user',
     'user',
     'post.title = :title',
     { title: 'title1' },
   )
   .where('user.id = :id', { id })
   .getOne();