InvalidOperationException when calling SaveChanges in .NET Entity framework

Question

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 ins

Answer 1

if you have a bindingsource bound, you should call the suspendbinding:

        bs.SuspendBinding();
        Data.SaveChanges();
        bs.ResumeBinding();

Answer 2

System.Data.Objects.SaveOptions.None

This solves the problem but I'm wondering what's the difference between uning none or the other options.

Answer 3

Check if Primary Keys are missing in any of your etities, if yes, then create them, and do the "UpdateModel from Database"

this should Solve the problem

Answer 4

I found the solution to this.

What happened was that when I created my table I forgot to add the primary key and set (Is Identity) property to yes. I then created my Entity model and got this error.

I went back and fixed my database table but I still hade the weird Exception. What solved the problem in the end was to remove the entity and re-create it after the table was fixed.

No more exceptions :)

Answer 5

I had the similar issue with table relationship spanning three levels Like Customer->Order->Order-Details with oracle 12C Auto-ID Trigger for key generation. Insertion using SaveChanges() was throwing System.InvalidOperationException.

Solution: Augmenting function SaveChanges(System.Data.Objects.SaveOptions.None) prevents system to use temporary EntityKeys in state of object graph and in result exception is avoided.

Answer 6

Also Check if you set the "Is Identity" property for another column to "yes" and you are inserting a duplicated values into it.