Question

So we copy and paste the exact same query from LinqPad into our EF 4.3 application, pointed at the exact same database and get a different result. In LinqPad we get 2 records returned. In our application we reaise an error “Object reference not set to an instance of an object.”

        var Shippings = shippingRepository.All.ToArray();
        var SalesOrderHeaders = salesOrderHeaderRepository.All.ToArray();
        var Customers = customerRepository.All.ToArray();
        var Stores = storeRepository.All.ToArray();
        var Departments = departmentRepository.All.ToArray();

        var toShip = from sh in Shippings
                     join h in SalesOrderHeaders on sh.OrderId equals h.SalesOrderHeaderId
                     join c in Customers on h.CustomerId equals c.CustomerId
                     join st in Stores on h.StoreId equals st.StoreId
                     join d in Departments on h.DepartmentId equals d.DepartmentId into outer
                     from o in outer.DefaultIfEmpty()
                     select new 
                     {
                        OrderId = sh.OrderId,
                        CustomerName = c.Name,
                        StoreName = st.Name,
                        DepartmentName = (o.Name == null) ? o.Name : "None",
                        DeliveryDate = h.DeliveryDateTime
                     };

In the application code, when we remove the outer join (to add Departments) and it’s associated field the query returns the same 2 records asn in LinqPad.

Does anyone have any insight into how to fix this feature?

Answer 1

Click on “Add a connection” in linqpad and select datacontext from assembly like

You can choose Entity Framework datacontext or Entity Framework BDContext with POCO depending upon your scenario. click next and provide path to the assembly along with connection string and you will be good to go.