A referential integrity constraint violation occurred

Question

I'm trying to update an existing entity.

I have the following code:

public MamConfiguration_V1 Save(MamConfiguration_V1 item)
{
    mMaMDBEntities.MamConfiguration_V1.Attach(item);
    mMaMDBEntities.ObjectStateManager.ChangeObjectState(item, System.Data.EntityState.Modified);
    mMaMDBEntities.SaveChanges();
    return item;
}

But the Attach methods throws an exception:

A referential integrity constraint violation occurred: The property values that define the referential constraints are not consistent between principal and dependent objects in the relationship.

How can I fix this?

Answer 1

What is the definition of the item object? It seems that in some of its collections that set the realionship with other entities exist some type of conflict. You could try to clear all the collections to see if the problem persists, but in this case you lost the foreign key assignment. But perhaps it could help you to locate the problem.

This could be a tip. When I try to attach an existing entity to the context, I use to do the following:

mMaMDBEntities.Entry<MamConfiguration>(item).State = System.Data.EntityState.Modified;

You can add the using of System.Data to avoid the needed to write it all the time.

This attach the entity in the state that you want, modified in this case and track the changes. This is one line instead of two.