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How to add mutiple entities for an attribute (iOS, Core Data)?

I want to create a one to many relationship. My setup is something like:

I have the Profile Entity, I have the Time entity.

Every profile has a relationship to Time.

How can I define relationships, and add multiple Time entities to a single profile?

I bet it is obvious, but I can't see how to implement.

edit after posting the answer I saw your comment - to define a to-many relationship in the modeller, select the relationship and choose to-many from the options:

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To populate the relationship, you can do it two ways. I am assuming your Profile entity has a to-many relationship called times and the inverse relationship is a to-one relationship called profile .

  • Set the profile on each Time entity as you are creating them. This will automatically populate the inverse relationship (ie add the Time to the times set of the profile).
  • Collect the relevant Time entities in a set and set the times property to this set. Again, the inverse will be automatically populated.

There is more information here . Accessor methods to add individual entities to a to-many relationship can be generated from the managed object model editor in Xcode.

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