为什么实体框架会抛出此错误？ [英] Why is entity framework throwing this error?

问题描述

ex.Message = "Unable to update the EntitySet 'ExternalEmployees' because it has a DefiningQuery and no <UpdateFunction> element exists in the <ModificationFunctionMapping> element to support the current operation."

if(externalEmployeeDataGrid.IsVisible)
                {
                    ExternalEmployee selectedEmployee = (ExternalEmployee)externalEmployeeDataGrid.SelectedItem;
                    ExternalEmployee ExtEmpContext = this.context.ExternalEmployees.Find(selectedEmployee.ID);

                    if(ExtEmpContext != null)
                    {
                        ExtEmpContext.BadgeNo = selectedEmployee.BadgeNo;
                        ExtEmpContext.EmployeeName = selectedEmployee.EmployeeName;
                        ExtEmpContext.EmployeeType = selectedEmployee.EmployeeType;
                        // ExtEmpContext.Status = selectedEmployee.Status;


                        
                        context.SaveChanges();
                    }
                }

这是实体设置......

Here is Entity setup...

public ExternalEmployee newExternalEmployee { get; set; }

       NewMealPlanEntities context = new NewMealPlanEntities();
       CollectionViewSource externalEmployeesViewSource;

       public ExternalEmployeesWindow()
       {
           InitializeComponent();

           externalEmployeesViewSource = ((CollectionViewSource)FindResource("externalEmployeeViewSource"));

           DataContext = this;
       }

       private void Window_Loaded(object sender, RoutedEventArgs e)
       {

           //System.Windows.Data.CollectionViewSource externalEmployeeViewSource = ((System.Windows.Data.CollectionViewSource)(this.FindResource("externalEmployeeViewSource")));
           // Load data by setting the CollectionViewSource.Source property:
           // externalEmployeeViewSource.Source = [generic data source]

           context.ExternalEmployees.Load();
           externalEmployeesViewSource.Source = context.ExternalEmployees.Local;

我的尝试：



我确实注意到一个错误，在早期，表明该表没有主键，但我更正了，删除了edmx，并重新生成了所有内容。



有趣的东西！ ：（

What I have tried:

I did notice an error, early on, indicating that the table does not have a primary key but I corrected that, deleted the edmx, and re-generated everything.

fun stuffs! :(

推荐答案

好的，

神圣粗心，蝙蝠侠！



我最初指向服务器连接到同一个表名所在的位置没有主键，所以实体是用只读表创建的。



幸运的是，我能够在指向正确的服务器后放弃EDMX并重新生成它。

OK,
Holy carelessness, Batman!

I had originally pointed server connection to where the same table name was located that did NOT have a primary key so entity was created with read-only table.

Fortunately, I was able to drop the EDMX and re-generate it after pointing to the correct server.

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