title: How to return only some columns of a relations with Typeorm
body: <p>Ok, i'm having trouble with getting the relations with typeorm, when i run the service it returns me all the data from the relation, and i want only specific fields, like id and name.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>async findById(id: string): Promise&lt;UsersUseOfferHistoric&gt; {
  return await this.repository.findOne({
    where: { id },
    relations: ['userId', 'offerId'],
    });
  }
  </code></pre>
  
  <p>Here's the json Output:</p>
  
  <pre><code>{
  "id": "da0fd04e-17c6-4412-b342-a4361d191468",
  "createdAt": "2020-01-07T19:48:30.840Z",
  "userId": {
      "id": "bdc00227-569f-44b5-9bdd-c8de03661ebd",
      "name": "Alexandre Vieira",
      "cpf": "10443771430",
      "email": "av.souza2018@gmail.com",
      "password": "asjdsifjdsfasf",
      "imagePath": "/me.png",
      "active": true,
      "lastLogin": "2020-01-07T19:40:26.850Z",
      "createdAt": "2020-01-07T19:40:26.850Z",
      "updatedAt": "2020-01-07T19:40:26.850Z"
  },
  "offerId": {
      "id": "e399560c-d2c2-4f4e-b2b1-94cae3af3779",
      "offerDrescription": "Nova oferta top",
      "discountCoupon": " Desconto top",
      "discountValidity": "2020-01-07T14:18:19.803Z",
      "discountPercentage": 20,
      "discountQuantityLimit": 50,
      "createdAt": "2020-01-07T19:45:33.589Z",
      "updatedAt": "2020-01-07T19:45:33.589Z"
     }
  }
  </code></pre>
  
  <p>Here's the output i want:</p>
  
  <pre><code>{
  "id": "da0fd04e-17c6-4412-b342-a4361d191468",
  "createdAt": "2020-01-07T19:48:30.840Z",
  "userId": {
      "id": "bdc00227-569f-44b5-9bdd-c8de03661ebd",
      "name": "Alexandre Vieira",
  
  },
  "offerId": {
      "id": "e399560c-d2c2-4f4e-b2b1-94cae3af3779",
      "offerDrescription": "Nova oferta top",
  
     }
  }
  </code></pre>