实体框架核心 - 拥有类型的修改键

Question

While saving changes in my database, an exception with the following message is returned:

The property 'OrderId' on entity type 'Order.CustomerDeliveryDetails#CustomerDetails' is part of a key and so cannot be modified or marked as modified. To change the principal of an existing entity with an identifying foreign key first delete the dependent and invoke 'SaveChanges' then associate the dependent with the new principal.

The database is implemented with entity framework core with a 'code first' approach. Order.CustomerDeliveryDetails is an owned type (of the type CustomerDetails ) of the entity Order . CustomerDetails has no property called OrderId . As I understand OrderId is a implicit key , generated by entity framework core as a shadow property .

The classes are structured as follows:

public class Order
{
    public int Id { get; set; }
    public CustomerDetails CustomerDeliveryDetails { get; set; }
}

[Owned]
public class CustomerDetails
{
    public string Street { get; set; }
}

The object is updated as follows:

var order = await orderContext.Orders
        .Where(o => o.Id== updateOrder.Id)
        .FirstOrDefaultAsync();

order.CustomerDeliveryDetails.Street = updateOrder.CustomerDeliveryDetails.Street;
await orderContext.SaveChangesAsync();

What I fail to understand is how OrderId can be modified, when it can't be accessed directly in the code.

The only thing I can think of which might cause this error, is the fact that this update is being run on a timed webjob in Azure. This is hunch is supported by the fact that the update passes the related unit tests. Could this have to do with a race condition ?

Update:

I'm fairly certain the error comes from some sort of race condition. The timed webjob loads a list of orders that need to be updated every 2 minutes. The update works fine as long as the list contains less then +-100 orders, but starts to fail once this list gets longer.

The webjob is probably inable to finish updating all the orders within 2 minutes if the list gets to long.

The context is added through dependency injection as follows:

serviceProvider.AddDbContext<OrdersContext>(options => options.UseSqlServer(ctx.Configuration["ConnectionString"], sqlOptions => sqlOptions.EnableRetryOnFailure()));

My best geuss is that the context is being shared between multiple calls of the webjob, which is causing the errors.

Answer 1

This boils down to your database relationships.Are you using database first or code first approach? How are the models defined? Whats the relationship between Order, CustomerDetails and the CustomerDeliveryDetails tables? Please provide the code and I will be able to help you with the solution.