Question

I’m trying to resolve an error very similar to the one outlined here:

InvalidOperationException when calling SaveChanges in .NET Entity framework

It appears that the solution (which I have not tried yet, admittedly) is to pass System.Data.Objects.SaveOptions.None as the SaveOptions parameter for the SaveChanges() method.

So before I do that, I’m trying to understand exactly how the different SaveOptions work (None, AcceptAllChangesAfterSave, DetectAllChanges). I haven’t been able to find a clear explanation of it however, nor am I sure what the default is. Can anyone clarify?

Thanks!

UPDATE: I have posted the actual problem question here: System.InvalidOperationException when trying to iteratively add objects using EF 4

Answer 1

In a nutshell (from what I understand):

SaveOptions.DetectChangesBeforeSave : this is the default. When you do ObjectContext.SaveChanges(), the method DetectChanges() is called to synchronized attach entities in the OSM.

SaveOptions.AcceptAllChangesAfterSave : When you do ObjectContext.SaveChanges(), the method AcceptAllChanges() is called – which is the guts of the OSM, where the entities in the graph are iterated, addresses and set to Unchanged/Detached.

SaveOptions.None : When you do ObjectContext.SaveChanges(), changes are saved immeditately – no synchronization at all. Whatever is in the graph is what will be saved.

In my experience I have not changed this – I’ve left it as the default (DetectChangesBeforeSave).

Sometimes with POCOs I have heard you need to explicitly call DetectChanges, but I’ve never seen a recommendation/solution to change the SaveOptions to none.

Are you sure the solution in that question is to set SaveOptions to none? Maybe you should provide detail (or ask a separate question) as to the error you’re getting, as a change like this will affect your entire persistence layer.