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Has and Belongs to Many with extra properties in link?

#1

If I wanted to do a has and belongs to many by the following object model:

        Object 1 ----------->> O1_O2_link <<------------------ Object 2

fields for link:
o1: Object 1
o2: Object 2
extraProp: String

where Object 1 and Object 2 have many O1_O2_link, is there any recommendations on:

  1. Fetching Object2’s as children of Object1, visa versa?
  2. add/remove Object2 to Object1, which would add the link as well? So create Object2 and then the link?

Is this all manually coded? Or is there some slicker way?

#2

@dskjflksjadlkfj Do you still have issues or have you managed to solve this in the meantime?

#3

Still have the issue - but I believe I wrote the issue incorrectly. Unable to close, please close and I’ll re-open.

#4

If you have an instance of Object1, it will have an Object2Link property, which is a list of link objects. So you can use that list to get at its Object2’s.

Or you can fetch just the link objects, with a predicate for Object1. You can then use each link object to get the properties of Object1, Object2, and the extraProp of the link.

Yes, create a new link, set the Object1, Object2, and extraProp properties, and save it.
To remove, find the link that matches what you want to remove, and delete the link.

closed #5

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