Calling DB Function with Entity Framework 6

Question

I followed these instructions to add a scalar function into my Entity Framework 6 data model. How to use scalar-valued function with linq to entity?

However, I\'m no

Answer 1

I found the answer. Although I could find very little documentation about Entity Framework 6 in which EdmFunctionAttribute is obsolete, I got this code to work.

In the EDMX file, IsComposable must be True and the CommandText must be removed. I need only the function declaration without the function import.

Then, in a partial class of my data context, I created this function

[DbFunction("NaturalGroundingVideosModel.Store", "fn_GetRatingValue")]
public float? DbGetValue(float? height, float? depth, float ratio) {
    List<ObjectParameter> parameters = new List<ObjectParameter>(3);
    parameters.Add(new ObjectParameter("height", height));
    parameters.Add(new ObjectParameter("depth", depth));
    parameters.Add(new ObjectParameter("ratio", ratio));
    var lObjectContext = ((IObjectContextAdapter)this).ObjectContext;
    var output = lObjectContext.
            CreateQuery<float?>("NaturalGroundingVideosModel.Store.fn_GetRatingValue(@height, @depth, @ratio)", parameters.ToArray())
        .Execute(MergeOption.NoTracking)
        .FirstOrDefault();
    return output;
}

I added the function to the MediaRating object so I can call it without needing a reference to the data context.

var Test2 = (from r in context.MediaRatings
    select r.DbGetValue(r.Height, r.Depth, 0)).ToList();

This works!