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LINQ Complied queries giving error : There is no implicit reference conversion from 'Chinook.ChinookModel' to 'System.Data.Entity.Core.Objects.ObjectContext'.


I have a class" Employee" and DBcontext : ChinookModel (.Net 4.5) , however when I try to create compiled query it gives the following error : ( Any help is appreciated, Thanks in advance )

The type 'Chinook.ChinookModel' cannot be used as type parameter 'TArg0' in the generic type or method 'System.Data.Entity.Core.Objects.CompiledQuery.Compile<TArg0,TArg1,TResult>(System.Linq.Expressions.Expression<System.Func<TArg0,TArg1,TResult>>)'. There is no implicit reference conversion from 'Chinook.ChinookModel' to 'System.Data.Entity.Core.Objects.ObjectContext'.
C:\Users\Bond009\documents\visual studio 2013\Projects\Chinook\Chinook\DAL\Queries.cs
I am using the following code to create LINQ complied query:

namespace Chinook
    public class StaticQueries
        static readonly Func<ChinookModel, int, IQueryable<Employee>> getemployeebyid =
           CompiledQuery.Compile<ChinookModel, int, IQueryable<Employee>>
           ((ctx, tempid) => from c in ctx.Employees
                             where c.EmployeeId == tempid
                             select c);

====================Employee Class ======================

    public partial class Employee
        public Employee()
            Customers = new HashSet<Customer>();
            Employee1 = new HashSet<Employee>();

        public int EmployeeId { get; set; }

        public string LastName { get; set; }

        public string FirstName { get; set; }

        public string Title { get; set; }

        public int? ReportsTo { get; set; }

        public DateTime? BirthDate { get; set; }

        public DateTime? HireDate { get; set; }

        public string Address { get; set; }

        public string City { get; set; }

        public string State { get; set; }

        public string Country { get; set; }

        public string PostalCode { get; set; }

        public string Phone { get; set; }

        public string Fax { get; set; }

        public string Email { get; set; }

        public virtual ICollection<Customer> Customers { get; set; }

        public virtual ICollection<Employee> Employee1 { get; set; }

        public virtual Employee Employee2 { get; set; }

=====================ChinookModel - Dbcontext =====================

public partial class ChinookModel : DbContext
        public ChinookModel()
            : base("name=Chinook")

        public virtual DbSet<Album> Albums { get; set; }
        public virtual DbSet<Artist> Artists { get; set; }
        public virtual DbSet<Customer> Customers { get; set; }
        public virtual DbSet<Employee> Employees { get; set; }
        public virtual DbSet<Genre> Genres { get; set; }
        public virtual DbSet<Invoice> Invoices { get; set; }
        public virtual DbSet<InvoiceLine> InvoiceLines { get; set; }
        public virtual DbSet<MediaType> MediaTypes { get; set; }
        public virtual DbSet<Playlist> Playlists { get; set; }
        public virtual DbSet<Track> Tracks { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
                .HasMany(e => e.Albums)
                .WithRequired(e => e.Artist)

                .HasMany(e => e.Invoices)
                .WithRequired(e => e.Customer)

                .HasMany(e => e.Customers)
                .WithOptional(e => e.Employee)
                .HasForeignKey(e => e.SupportRepId);

                .HasMany(e => e.Employee1)
                .WithOptional(e => e.Employee2)
                .HasForeignKey(e => e.ReportsTo);
        public int ThisID { get; set; }
Avatar of Karrtik Iyer
Karrtik Iyer
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May I please know why is this a grade B, I have explained the reason why error was coming and what are the possible way to solve it?
Avatar of Explorer JK
Explorer JK


My bad ....I am new to this grading.. system....please change to A... Thanks Karrtik.