EF Core Foreign Key Enum-to-Primitive Conversion Issue: "Cannot target primary key because it is not compatible"

[yousafzainasir9]

I have mapped field to following this. video
entities generated now have enum mapping, but when I try to fetch, I get a runtime error.
basically, my enum field is a foreign key reference.

The relationship from 'TempEntity.TempReferenceEntity' to 'TempReferenceEntity.TempEntities' with foreign key properties {'TempEnumID' : TempEnumType} cannot target the primary key {'TempEnumID' : short} because it is not compatible. Configure a principal key or a set of foreign key properties with compatible types for this relationship.

my enum is of type short EvidenceTypeEnum

also I am generating the conversion

  modelBuilder.Entity<TempEntity>(entity =>
  {
      entity.Property(e => e.TempEnumID)
          .HasConversion<short>() // Converts enum to short
          .HasColumnType("smallint") // Matches the database type
          .IsRequired();
  
      entity.HasOne(d => d.TempReferenceEntity)
          .WithMany(p => p.TempEntities)
          .HasForeignKey(d => d.TempEnumID)
          .OnDelete(DeleteBehavior.ClientSetNull)
          .HasConstraintName("FK_TempEntity_TempReferenceEntity");
  });

is the enum code

public enum TempEnumType : short
{
    TypeA = 1,
    TypeB = 2,
    TypeC = 3
}

public class TempEntity
{
    public int TempEntityID { get; set; } // Primary Key
    public TempEnumType TempEnumID { get; set; } // Foreign Key
    public virtual TempReferenceEntity TempReferenceEntity { get; set; } // Navigation Property
}

public class TempReferenceEntity
{
    public short TempEnumID { get; set; } // Primary Key
    public string Name { get; set; }
    public virtual ICollection<TempEntity> TempEntities { get; set; } // Navigation Property
}

[ErikEJ]

I assume the current solution does not work if the column if a foregin key

[ErikEJ]

I have updated the docs here

[yousafzainasir9]

In order to make it work, I have updated the Primary Key to the enum as well, in this way I am able to set Foreign Key as enum.

public enum TempEnumType : short
{
    TypeA = 1,
    TypeB = 2,
    TypeC = 3
}

public class TempEntity
{
    public int TempEntityID { get; set; } // Primary Key
    public TempEnumType TempEnumID { get; set; } // Foreign Key
    public virtual TempReferenceEntity TempReferenceEntity { get; set; } // Navigation Property
}

public class TempReferenceEntity
{
    public TempEnumType  TempEnumID { get; set; } // Primary Key
    public string Name { get; set; }
    public virtual ICollection<TempEntity> TempEntities { get; set; } // Navigation Property
}

[ErikEJ]

Great, and thanks for sharing.

If you like my free tools, I would be very grateful for a rating/review on Visual Studio Marketplace and/or a one-time or monthly sponsorship