InvalidOperationException when calling SaveChanges in .NET Entity framework
- by Pär Björklund
Hi, I'm trying to learn how to use the Entity framework but I've hit an issue I can't solve.
What I'm doing is that I'm walking through a list of Movies that I have and inserts each one into a simple database.
This is the code I'm using
private void AddMovies(DirectoryInfo dir)
{
MovieEntities db = new MovieEntities();
foreach (DirectoryInfo d in dir.GetDirectories())
{
Movie m = new Movie { Name = d.Name, Path = dir.FullName };
db.AddToMovies(movie);
}
db.SaveChanges();
}
When I do this I get an exception at db.SaveChanges() that read.
The changes to the database were
committed successfully, but an error
occurred while updating the object
context. The ObjectContext might be in
an inconsistent state. Inner exception
message: AcceptChanges cannot continue
because the object's key values
conflict with another object in the
ObjectStateManager. Make sure that the
key values are unique before calling
AcceptChanges.
I haven't been able to find out what's causing this issue.
My database table contains three columns
Id int autoincrement
Name nchar(255)
Path nchar(255)
Update:
I Checked my edmx file and the SSDL section have the StoreGeneratedPattern="Identity" as suggested. I also followed the blog post and tried to add ClientAutoGenerated="true" and StoreGenerated="true" in the CSDL as suggested there. This resulted in compile errors ( Error 5: The 'ClientAutoGenerated' attribute is not allowed.). Since the blog post is from 2006 and it has a link to a follow up post I assume it's been changed.
However, I cannot read the followup post since it seems to require an msdn account.
