Home/ Questions/Q 8760141
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-13T14:58:18+00:00

I am confused about aggregate objects and that only aggregate objects have repositories because

  • 0

I am confused about aggregate objects and that only aggregate objects have repositories because I don’t know how to properly code it.

Assume that you have a User, Question and QuestionLog entity. I don’t understand how to set the boundaries for how much you should put in an aggregate object. You could say that no questions would live in my system without a user, and a questionlog would not exist if it had no questions to be attached to. So would user be an aggregate root?

How would you add a questionlog then for instance?
For me it seems like you end up with a lot of nesting etc. User.addQuestionLog? I don’t understand where the boundaries go for when it should be an aggregate and seen as a unit? For me it would be more natural that User is one aggregate and Question is another. However I don’t understand how to actually know this.

And a question can have categories too, would the category also be a part of question or not? Why/why not? How to spot them?

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Don’t think of the objects, DDD is all about real life.

    The real questions are:

    • Can X exist whithout Y?
    • Is Y a part of X?

    Hence:

    • Can a user exist without a question? Yes
    • Should the question still be available if the user quits? Yes
    • Is a log part of a user? No
    • Is a log part of a question? No (since it belongs to users, but is not part of a user)
    • Is a category part of a question? Typically yes

    So we end up with three root aggregates.

    The category is value object

    • 0