Entity Framework - Seed AddOrUpdate with multi column index as identifier

Question

I am trying to seed a database using the context.AddOrUpdate method, but the problem is that I need to make the inserted data unique based on a multi column index.

[Table("climbing_grades")]
public class ClimbingGrade : EntityBase
{
    /// <summary>
    /// The name of the climbing grade, e.g.: 7a, VII, etc.
    /// </summary>
    [Index("IX_Name_GradeType", 1, IsUnique = true)]
    public string Name { get; set; }

    /// <summary>
    /// Tries to display the average difficulty of the described grade.
    /// Matching the different grades can be difficult because its always
    /// a subjective rating and there exists no norm on converting grades.
    /// </summary>
    public double Difficulty { get; set; }

    /// <summary>
    /// The type of the grade. Will be the respective region rating.
    /// e.g.: UUIA for most oft europe, YSD for USA, etc.
    /// </summary>
    [Index("IX_Name_GradeType", 2, IsUnique = true)]
    public ClimbingGradeType GradeType { get; set; }
}

Currently I AddOrUpdate based on the Name of the climbing grade, but now I am at a point where I need to insert duplicate names.

context.ClimbingGrades.AddOrUpdate(grade => /* Compare multi column index here?*/,
    new ClimbingGrade
    {
        Name = "5a",
        Difficulty = 4.75,
        GradeType = ClimbingGradeType.FontainebleauBloc
    },
    new ClimbingGrade
    {
        Name = "5a",
        Difficulty = 4.25,
        GradeType = ClimbingGradeType.FontainebleauTraverse
    });

Is it possible to compare multi column indexes when I insert seed data?

Unscrupulous

What do you mean by "is it possible to compare...?" What do you exactly want to do? Do you want to only keep some of the possible repeated values? – Xanthippe

I want to use the multi column index as a reference if the data set already exists in the database. e.g.: .AddOrUpdate(grade => grade.Name == existing.Name && grade.GradeType == existing.GradeType) – Unscrupulous

Answer 1

You need to use anonymous type for specifying multiple columns. This also works without specifying the indicies.

context.ClimbingGrades.AddOrUpdate(grade => new { grade.Name, grade.GradeType },
    new ClimbingGrade
    {
        Name = "5a",
        Difficulty = 4.75,
        GradeType = ClimbingGradeType.FontainebleauBloc
    },
    new ClimbingGrade
    {
        Name = "5a",
        Difficulty = 4.25,
        GradeType = ClimbingGradeType.FontainebleauTraverse
    });

Hashim