We help IT Professionals succeed at work.
Get Started

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

Explorer JK
Explorer JK asked
on
431 Views
Last Modified: 2016-10-31
Hi,

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 )

Error
1
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
18
12
Chinook
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 ======================

    [Table("Employee")]
    public partial class Employee
    {
        public Employee()
        {
            Customers = new HashSet<Customer>();
            Employee1 = new HashSet<Employee>();
        }

        public int EmployeeId { get; set; }

        [Required]
        [StringLength(20)]
        public string LastName { get; set; }

        [Required]
        [StringLength(20)]
        public string FirstName { get; set; }

        [StringLength(30)]
        public string Title { get; set; }

        public int? ReportsTo { get; set; }

        public DateTime? BirthDate { get; set; }

        public DateTime? HireDate { get; set; }

        [StringLength(70)]
        public string Address { get; set; }

        [StringLength(40)]
        public string City { get; set; }

        [StringLength(40)]
        public string State { get; set; }

        [StringLength(40)]
        public string Country { get; set; }

        [StringLength(10)]
        public string PostalCode { get; set; }

        [StringLength(24)]
        public string Phone { get; set; }

        [StringLength(24)]
        public string Fax { get; set; }

        [StringLength(60)]
        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)
        {
            modelBuilder.Entity<Artist>()
                .HasMany(e => e.Albums)
                .WithRequired(e => e.Artist)
                .WillCascadeOnDelete(false);

            modelBuilder.Entity<Customer>()
                .HasMany(e => e.Invoices)
                .WithRequired(e => e.Customer)
                .WillCascadeOnDelete(false);

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

            modelBuilder.Entity<Employee>()
                .HasMany(e => e.Employee1)
                .WithOptional(e => e.Employee2)
                .HasForeignKey(e => e.ReportsTo);
        }
        public int ThisID { get; set; }
    }
======================================================
Comment
Watch Question
Software Architect
Commented:
This problem has been solved!
Unlock 1 Answer and 4 Comments.
See Answer
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE