Question

In my WCF web service I have been reading from the database with no trouble at all. Today I attempted an update but quickly discovered the changes weren’t actually being saved to the database. I am getting no errors or exceptions thrown. I have spent the last several hours researching the problem with no luck. I have found many similar questions but most of he time the reason was that the table being written to didn’t have a primary key, however this is not the case with this table.

Here’s some code:

var db = new dbDataContext(Convert.ToString(ConfigurationManager.AppSettings["sConn"]));

...


        var bookingRow = (from mBooking in db.d_bookings
                          where mBooking.booking_id == bookingID
                          select new BookingResult
                          {
                              guideID = mBooking.user_id_guide == null ? 0 : (int)mBooking.user_id_guide,
                              adultShow = mBooking.booking_nAdults_show == null ? 0 : (int)mBooking.booking_nAdults_show,
                              childShow = mBooking.booking_nChild_show == null ? 0 : (int)mBooking.booking_nChild_show,
                          }
                          ).Single();

        bookingRow.guideID = someNewValue;
        bookingRow.adultShow = someNewValue;
        bookingRow.childShow = someNewValue;

        try
        {
            db.SubmitChanges();
        }
        catch (Exception ex)
        {
            return "{\"result\" :  \"false\" }";

        }

And the BookingResult class is simply:

public class BookingResult
{
    public int guideID { get; set; }
    public int adultShow { get; set; }
    public int childShow { get; set; }
}

This is my first project working with WCF and LINQ and it seemed incredibly straight forward for the most part but this has thrown me for a loop. Any help is greatly appreciated!

SOLVED: The problem was that I was reading into the custom class which wasn’t attached to my DataContext. Removing the class and just selecting the entire row works fine.

var bookingRow = (from mBooking in db.d_bookings
                      where mBooking.booking_id == bookingID
                      select mBooking
                  ).Single();

Answer 1

You’re creating a completely new BookingResult that would not be attached to the DataContext and therefore will not be considered as a change when you call SubmitChanges. Is there a table in the database called BookingResults? What do you hope will happen to your new BookingResult? Would it create a new row?