typeorm 内联/外联

表

import { Column, Entity, ManyToOne, PrimaryGeneratedColumn } from "typeorm";
import { UserEntity } from "./user.entity";
@Entity('content_1')
export class Content {
    @PrimaryGeneratedColumn()
    id: number;
    @Column()
    name: string
    //  本表多个 查询 user表一个
    @ManyToOne(() => UserEntity, user => user.content)
    user: UserEntity
}

外联

LEFT JOIN 外联。如果user里面没有值，也会返回content数据

return await getRepository(Content)
  .createQueryBuilder('content')
  .leftJoinAndSelect('content.user','user')    //    外联
  .where('content.name = :name',{name:333})
  .getMany()
//    查询到的数据
{
    "code": 2000,
    "message": "请求成功!",
    "time": "2021-03-21T05:32:08.898Z",
    "data": [
        {
            "id": 3,
            "name": "333",
            "user": null
        }
    ]
}

内联

INNER JOIN 内联，如果user里面没有数据，则不显示content数据

return await getRepository(Content)
  .createQueryBuilder('content')
  .innerJoinAndSelect('content.user','user')    //    内联
  .where('content.name = :name',{name:333})
  .getMany()
//     查询到的结果
{
    "code": 2000,
    "message": "请求成功!",
    "time": "2021-03-21T05:33:56.349Z",
    "data": []
}