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c#sqlentity-frameworkauto-generate

Self-Referencing FK Generating Strangly

In the screenshot below is an Entity (URL) in my model. The ParentId field is a self-referencing FK (points to Url.Id). You can see this navigation at the bottom of the screenshot.

alt text

In my SQL and my DB, which I generate the EDMX from, the self-referencing FK is called FK_Urls_Parent:

-- Creating foreign key on [ParentId] in table 'Urls'
ALTER TABLE [Urls]
ADD CONSTRAINT [FK_Urls_Parent]
    FOREIGN KEY ([ParentId])
    REFERENCES [Urls]
        ([Id])
    ON DELETE NO ACTION ON UPDATE NO ACTION;

My questions are:

  1. Why did EF generate Urls1 and Url1 just from that one FK? Url1 is a 0 or 1 property that is 'FromRole' Urls1. Urls1 is 'FromRole' Urls 'ToRole' Urls1. It seems like EF is making a navigation property that is the exact same as Url table. Why would it do this and can I do something to make it just generate the one, desired Navigation property: Urls1?
  2. Okay, so not quite as important, but can I control the name of the Navigation property based on the FK name or something in the DB? I hate that it names it 'Url1'. I would prefer 'Parent', but don't want to have to manually change it in the designer every time I regenerate the model.

Thanks.

Solution

  • It is modeling both sides of the relationship. In other words, one of the properties will be the entry being pointed to by this entry's ParentId. The other will be the entry(s) whose ParentId field points to this entry. You can disable one side in the relationship properties, or rename them to make sense. Such as, for instance, ParentUrl and ChildUrls.

    I'm not 100% certain how to get to the property relation dialog without opening the program myself, which I can't right now. I do know for me it appears in the (by default) bottom-right properties window when the link is selected.

    As far as making this change somehow permanent across model regenerations, I know of no way to do this. Hopefully someone else will know, because it would save me a lot of time too!