Core Data modelling question re: OutlineEdit example

  • I have a probably silly question re: the data model editor in XCode
    2.4.1.

    Why is the "priority" relationship represented visually with a
    connecting line between the Note and Priority entities, but there
    isn't one for children and parents?

    I'm confused because when I made a similar data model in another
    project that had a parent and children relationship, I saw connecting
    lines back to the entity, and was wondering if I was missing
    something...

    Thanks.

    --> Michael B. Johnson, PhD
    --> http://homepage.mac.com/drwave (personal)
    --> http://xenia.media.mit.edu/~wave (alum)
    --> MPG Lead
    --> Pixar Animation Studios
  • > Why is the "priority" relationship represented visually with a
    > connecting line between the Note and Priority entities, but there
    > isn't one for children and parents?

      ??? Are you referencing an illustration you tried to attach? If so,
    it didn't make it. :-) I don't think attachments are allowed on the
    list. Do you have a URL to a shared copy?

    > I'm confused because when I made a similar data model in another
    > project that had a parent and children relationship, I saw connecting
    > lines back to the entity, and was wondering if I was missing
    > something...

      This is just a guess (since I have no idea to what you're
    referring), but pehraps you haven't defined both sides of the
    relationship and / or specified one as the inverse to the other.

      In other words:

    Parent (children->)  <------>> (<-parent) Child

      You have to specify the "children" relationship as pointing to
    (to-many) Child, then specify the "parent" relationship as pointing to
    the parent. On either one of those relationships, specify the opposite
    as the "Inverse" relationship.

      Hope this helps.

    --
    I.S.
  • On Oct 10, 2007, at 11:46 AM, I. Savant wrote:

    >> Why is the "priority" relationship represented visually with a
    >> connecting line between the Note and Priority entities, but there
    >> isn't one for children and parents?
    >
    > ??? Are you referencing an illustration you tried to attach? If so,
    > it didn't make it. :-) I don't think attachments are allowed on the
    > list. Do you have a URL to a shared copy?

    Sorry - I wasn't clear enough.

    I'm specifically talking about the OutlineEdit example in /Developer/
    Examples/OutlineEdit/

    If you bring up XCode on it the datamodel it should be clear what I'm
    talking about.

    --> Michael B. Johnson, PhD
    --> http://homepage.mac.com/drwave (personal)
    --> http://xenia.media.mit.edu/~wave (alum)
    --> MPG Lead
    --> Pixar Animation Studios
  • On 10/10/07, Michael B Johnson <wave...> wrote:
    > Sorry - I wasn't clear enough.
    > I'm specifically talking about the OutlineEdit example in /Developer/
    > Examples/OutlineEdit/

      Bah! I apologize; I completely missed the subject line. :-)

    > If you bring up XCode on it the datamodel it should be clear what I'm
    > talking about.

      Ah, I see what you mean now. Every time I've done the same, a line
    would protrude from the entity and point back toward itself. I'm not
    sure why it's not doing so there.

      If I delete the Note entity from the example's model, then recreate
    it exactly as before, the lines appear. If I close it and re-open it,
    it works fine. I'm willing to chalk this up to a bug in the data
    modeler.

      File a bug report.

    --
    I.S.
previous month october 2007 next month
MTWTFSS
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31        
Go to today