>>>>>>>>Thanks. I found that using Reflection I was able to have my ExcelWrapper SaveLinq Of T. Turned out easier than I thought.
>>>>>>>>
>>>>>>>>Slightly off topic and as Cetin pointed out to me, I should make use of the relationships so my Linq now looks like this:
>>>>>>>>

>>>>>>>>        public static void GetTransactions()
>>>>>>>>        {
>>>>>>>>            using (var context = new PICSEntities(Config.model.SqlServer))
>>>>>>>>            {
>>>>>>>>                var q = (from p in context.Parcels
>>>>>>>>                         join t in context.TransactionDetails on p.Parcels_Id equals t.Parcels_Id
>>>>>>>>                         select new
>>>>>>>>                         {
>>>>>>>>                             Parcels_Id = p.Parcels_Id,
>>>>>>>>                             Goods = p.GoodsType.Description,
>>>>>>>>                             Inventory = p.ParcelInventoryType.Description,
>>>>>>>>                             RSReference = p.RSReference,
>>>>>>>>                             Transaction_Nr = t.TransactionHeaders_Id,
>>>>>>>>                             Transaction = t.TransactionHeader.TransactionType.Description,
>>>>>>>>                             Date = t.TransactionHeader.TransactionDate,
>>>>>>>>                             Weight = t.Weight,
>>>>>>>>                             Amount = t.Amount,
>>>>>>>>                             EM_Document = t.TransactionHeader.EMTransactions.FirstOrDefault().Document ?? "",
>>>>>>>>                             EM_Count = t.TransactionHeader.EMTransactions.Count(),
>>>>>>>>                             RS_Type = t.TransactionHeader.RSTransactions.FirstOrDefault().RSTransactionType.Description ?? "",
>>>>>>>>                             RS_Document = t.TransactionHeader.RSTransactions.FirstOrDefault().Document ?? "",
>>>>>>>>                             RS_Count = t.TransactionHeader.RSTransactions.Count()
>>>>>>>>                         }).ToList();               
>>>>>>>>                using (var xl = new ExcelWrapper())
>>>>>>>>                {
>>>>>>>>                    xl.wb = xl.wbs.Add();
>>>>>>>>                    xl.ws = xl.wb.ActiveSheet;
>>>>>>>>                    string filename = SequencedFilename.get(@"c:\docs\Parcels", $".xlsx");
>>>>>>>>                    xl.SaveLinq(q, filename);
>>>>>>>>                }
>>>>>>>>            }
>>>>>>>>        }
>>>>>>>>

>>>>>>>>
>>>>>>>>This now works fine. I am a little bit worried about this though:
>>>>>>>>
>>>>>>>>

>>>>>>>>                            RS_Type = t.TransactionHeader.RSTransactions.FirstOrDefault().RSTransactionType.Description ?? "",
>>>>>>>>                             RS_Document = t.TransactionHeader.RSTransactions.FirstOrDefault().Document ?? "",
>>>>>>>>

>>>>>>>>
>>>>>>>>There is a 1 to M relation between TransactionHeaders and RSTransactions. But I'm really only interested in the first record, but I need two fields (Description and Document). The fact that I issue twice FirstOrDefault does not look right.
>>>>>>>>
>>>>>>>>Many thanks for your help.
>>>>>>>
>>>>>>>Don't see an easy way of avoiding the duplication but the code should be fine. But if TransactionHeader can have NO RSTransactions you will get an exception (ditto if no EMTransactions)
>>>>>>
>>>>>>Nono, it works fine. Coalescence ?? "" ?.
>>>>>
>>>>>That would work if (for example) RSTransactionType.Description was null. Won't if there is no first RSTransaction (i.e. if FirstOrDefault() returns null)
>>>>
>>>>Well ... Could it be that EF takes care of that ? I don't have a clue, but it does work.
>>>
>>>Doesn't take care of if for me :-{
>>>If FirstOrDefault() returns null than trying to access any property of the expected type throws a NullReferenceException
>>
>>Strange no? The Count is zero, but the linq does not break. Maybe there's a DefaultIsEmpty that is set to the type somewhere up the line? But then you would expect count() to return 1 no? TransactionHeaders is of DbSet type. Puzzling, but should I worry? :)
>
>Yup. Strange :-}
>TBH I've not used 'joins' much in Linq to EF - much prefer specifying associations. But I thought DefaultIfEmpty() is normally only used with left outer joins (and even then must be included in the code).
>But if it works and your happy - hey......

Specifying associations that's code first right. Not grown up enough here for that. But in fact that sets foreing keys in the db, which is the same as what I did, only I do db first. I use associations as well then no? I need the Join because there is an m to m relationship between parcels and transactions details. RsTransactions and EMTransactions have relationships in Header (or is that the other way around).

But basically then that should work for you too as the EF has generated the same code no, or am missing something?