Question

I ran into this error message while using EF5. Wondering if anyone has the answer for this.

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Budget.Data
{

    [Table("BudgetItems")]
   public class BudgetItemRepository
    {
         [Column("MdaCode")]
        public int MDACode { get; set; }
        [Column("PersonalCost")]
        public double PersonnelCost { get; set; }
        [Column("OverheadCost")]
        public double OverheadCost { get; set; }
        [Column("RecurrentCost")]
        public int RecurrentCost { get; set; }
        [Column("CapitalCost")]
        public double Capital { get; set; }

        public double Allocation { get; set; }
        [Column("BudgetYear")]
        public String BudgetYear { get; set; }
         [Column("RecordCreatedDate")]
        public DateTime DateCreated { get; set; }
        [Column("RecordLastModifiedDate")]
        public DateTime LastModifiedDate { get; set; }

        public virtual IList<BudgetItemRepository> budgetitems { get; set; }

        public virtual IList<BudgetLineItemRepository> budgetlineitems { get; set; }
         [Column("BudgetItemID")]
        public int Id { get; set; }
    }
}

Answer 1

You didn’t declare a primary key for the entity. You do this by marking the primary key column with the [Key} attribute. Assuming this is the Id property, the code would look like:

[Column("BudgetItemID")]
[Key]
public int Id { get; set; }