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Thread: [RESOLVED] Entity Framework Code First Hierarchical Many To Many Relationship

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    Resolved [RESOLVED] Entity Framework Code First Hierarchical Many To Many Relationship

    I don't know if this should go into the database development, but here it is:

    I have a model which essentially is a many to many relationship of itself. Sort of like below:

    Code:
    class Item
    
    int id;
    string name;
    IList<Item> ParentItems;

    It's basically an item which could be linked to another item as either a parent or a child. So each item could have more than one parent items (shared item) or it could have more than one child items.

    I tried creating a database out of this, but there's just a single Item table with an Item_ID property. Normally in a database, this type of a relationship would require two tables, one the Item table and the other a relationship table:

    Item: ID, Name
    ItemRelation: ItemID, ParentItemID

    How do I change the model to create the above setup? At present no matter what I can only do a one to one mapping.

    Edit: Found the solution. Here's my model which creates a many to many hierarchical relationship on the same table:

    Code:
    public class Item
    {
        public virtual int id { get; set; }
        public virtual string name { get; set; }
        public virtual IList<Item> ParentItems { get; set; }
        public virtual IList<Item> ChildItems { get; set; }
    }
    .
    Last edited by honeybee; Apr 4th, 2012 at 07:27 AM. Reason: Found solution
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