Some linq queries don't work in lightswitch

Question

I wrote many linq statments and they work just fine in lightswitch.

But recently I've been pulling my hair out for days trying to work out one LINQ query , and even try it using LinqPad tool, since I rely heavily on using the linqPad tool to make sure that my linq queries are accurate.

I have a feeling that there is a bug in lightswitch when readinf some linq query.

Is there any body experiencing this same issue?

Thanks,

Rachida

---

Rachida Dukes

Answer 1

can you post the query that gives trouble ?

---

paul van bladel

Answer 2

Thanks Paul for taking the time the help, this is the linq query I'm using:

  I have two tables Orders (Parent table) and FactoryOrders (Child table), they're linked by OrderKey which the primary field in the Orders table.

public IQueryable<SalesmanOrders> GetAllOrdersWithSaleman()

        {

           

            var FactoryOrdersCol = from f in ObjectContext.FactoryOrders

                                   join o in ObjectContext.Orders on f.OrderKey equals o.OrderKey

                                 

                                   select new SalesmanOrders

                                   {

                                    OrderID = o.OrderKey,

                                    OrderDate = o.OrderDate,

                                    ClientName = o.Client.ClientName,

                                    JobName = o.JobName,

                                    Commission = f.Commission.Value,

                                    SalesAmount = f.SalesAmount.Value,

                                   };

    }

public class SalesmanOrders

    {

        [Key]

        public string myID { get; set; }

        public int OrderID { get; set; }

        public DateTime OrderDate { get; set; }

       public string ClientName { get; set; }

        public string JobName { get; set; }

       public decimal SalesAmount { get; set; }

        public decimal Commission { get; set; }

    }

I'm using myID field in this query, I'm keeping until for later use.

Thanks again for your help.

Rachida

---

Rachida Dukes

Answer 3

Do you get back zero SalesmanOrders?

If so, lazy loading might be disabled.

Also, it might be possible to rewrite your query without a join by using navigation properties.

Answer 4

This doesn't look like something you'd write in LightSwitch. This looks more like a LINQ query that you would write in a RIA Service.

It would be helpful if you described what the problem actually is instead of just leaving it at "there's a problem". If an exception occurs, telling us what that exception is and what the call stack is when the exception occurs is extremely useful.

---

Justin Anderson, LightSwitch Development Team

Answer 5

I was able to find what the problem, I use this statment and it works:

var EntityCol = from o in ObjectContext.Orders
                            from f in ObjectContext.FactoryOrders
                            where  o.OrderKey == f.OrderKey
                            select new TempEntity
                            {
                                myID = f.FactoryOrderID,
                                FactoryOrderID =f.FactoryOrderID,
                                OrderID = o.OrderKey,
                                OrderDate = o.OrderDate,
                                Commission = f.Commission.Value,
                                SalesAmount = f.SalesAmount.Value,
                            };
                 return EntityCol;

 public class TempEntity
    {
        [Key]
        public int myID { get; set; }
        public int FactoryOrderID { get; set; }
        public int OrderID { get; set; }
        public DateTime OrderDate { get; set; }
        public decimal SalesAmount { get; set; }
        public decimal Commission { get; set; }

    }

---

Rachida Dukes