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Editorial Team
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Asked: 2026-06-06T00:11:13+00:00

I have a self-referential table in my database that looks sort of like above.

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Sample Table

I have a self-referential table in my database that looks sort of like above. Basically its setup in such a way that each row has a unique ID (identity PK) and a DependentID to indicate any other record in the set that it is dependent on. It is very similar to the parent-child type examples you often see in SQL textbooks but my case is subtly unique in the sense that a given record can also be dependent upon itself (see row 1 above)

Two questions:

  1. Can EF be made to represent this relationship properly? I’ve read several posts on here that suggest that it does not deal with this scenario gracefully so my initial thought was that it might not even be worth it, I might be better off just treating it as a normal table and writing the business logic to ensure the data gets inserted/updated correctly. In my scenario, I won’t ever be querying these entities thru EF really, the app will basically load them all at startup and then I’ll run linq queries against them at runtime to filter as needed

  2. Assuming I cannot get it to work with EF and as I note in #1 I simply load em all up into memory at startup (there are only going to be 50-100 or so), what would be the most efficient way to join on this via linq? I would want to be able to pass in a DependentId and get all the records associated with it and their properties…so in this example I’d want to pass in ‘1’ and get back:

1 – John – 10

2 – Mike – 25

3 – Bob – 5

thanks for the help

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1 Answer

  1. Editorial Team

    Indeed, the entity framework cannot represent such a relationship, certainly not in in a recursively queryable form.

    But you are not asking for recursive queries, so you could treat DependentId as just another data column. Doing that, it would be trivial to build and execute your question-two query against the database.

    UPDATE:

    That query would look something like

    int dependentIdToSearch = 1;

var q = from something in db.mytable
        where something.DependentId == dependentIdToSearch
        select new { something.Id, something.Name, something.Value };

    END UPDATE

    If you do need recursive queries (all direct and indirect dependencies of), you need a table valued function with a common table expression. The entity framework cannot deal with that either, at least not in the current version. If you need this support, you can wait for EF 5 or use Linq to SQL (which had support for table valued functions since the first version years ago).

    You can indeed also read the entire table in memory, provided that it is read-only, or that there is only “one memory” (single server, not load-balanced or client app with local database).

    If it’s read-only, you have the option to build an object graph once at load time, enabling efficient execution later. For example, you could define a class with a collection of objects that are dependent on each object. Your query then becomes a trivial iteration over that collection.

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