Question

I am currently running an app with a very LONG Linq transaction. Everything has to happen in this one transaction, and I’m not sure if or where objects are interfering with each other.

When I try to save the changes I see this warning come up:

System.InvalidOperationException: 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 t he key values are unique before
calling AcceptChanges.

From what I’ve read googling around, people have found a lot of one-off solutions (rarely having anything to do with conflicting keys), and they don’t usually post what the tip-offs are (better than nothing, of course).

What I’m not clear on is how do I hunt down the cause of this problem?

I update a lot of records in different places and let them go out of scope. I’m guessing the .NET compiler knows how to keep track of these objects without letting them go through the GC so it can commit everything at the end. And all the changes seem to end up in the database afterword.

Example:

            // create new A, SA for new incoming tasks
            SF_SUB_AREA sa = null;
            SF_AREA a = null;
            if (isNewSA)   // new SA
            {
                areaID = MakeSalesForceGUID();
                a = new SF_AREA
                {
                    ID = areaID,
                    DESCRIPTION = t.DESCRIPTION,
                    CU_NUMBER = Convert.ToString(t.CU_NUMBER),
                    FC = t.FC,
                    PROJECT = cp.ID,
                    DELETE_FLAG = "I"
                };
                ctx.SF_AREA.AddObject(a);


                SAID = MakeSalesForceGUID();
                sa= new SF_SUB_AREA
                {
                    ID = SAID,
                    PROJECT_REGION = t.CR,
                    AREA = areaID,
                    DELETE_FLAG = "I"
                };
                ctx.SF_SUB_AREA.AddObject(sa);
            }
            else       // old SA
            {
                List<SF_AREA> lia = (from a2 in ctx.SF_AREA
                                             join a2 in ctx.SF_SUB_AREA on a2.ID equals sa2.AREA
                                             where sa2.ID == t.SUB_AREA
                                             select ct2).ToList();
                if ((lia != null) && (lia.Count > 0))
                {
                    a = lia[0];
                    a.DELETE_FLAG = "U";
                    a.CLIENT_UNIT_NUMBER = Convert.ToString(t.CU_NUMBER);
                    a.DESCRIPTION = t.DESCRIPTION;
                    a.FC = t.FC;
                    a.PROJECT = cp.ID;
                } // TODO: throw an error here for else block

                List<SF_SUB_AREA> lisa = (from sa2 in ctx.SF_SUB_AREA
                                                              where sa2.ID == t.SUB_AREA
                                                              select sa2).ToList();
                if ((lisa != null) && (lisa.Count > 0))
                {
                    sa = lisa[0];
                    sa.PROJECT_REGION = t.AREA;
                    sa.AREA = lisa[0].AREA;
                    sa.DELETE_FLAG = "U";
                }
            }
            ...
            ctx.SaveChanges(); // left out the try/catch

Currently I’m just creating new context every time I commit something, but I don’t know if this is advisable.

            foreach (SF_MOVE_ORDER mo in liMO ) {
                using (SFEntitiesRM ctx2 = new SFEntitiesRM())  // new context for every MO since it goes into an unknown state after every commit
                {
                    List<SF_CLIENT_PROJECT> liCP = (from cp in ctx2.SF_CLIENT_PROJECT
                                                    where cp.ID == mo.CLIENT_PROJECT
                                                    select cp).ToList();
                    if ((liCP != null) && (liCP.Count > 0))
                    {
                        PerformMoveOrder(mo, liCP[0], ctx2);
                    }
                }
            }

Answer 1

Usually with errors like this, it is best to start out by saving one object and building in the complexities one at a time. That way, you can start to figure out where the problem lies. It can end up being somewhere down the object graph that you weren’t even expecting. But I would not just continue to throw the whole LINQ update at the context. Break it up into smaller saves and rebuild it to the largets graph and you’ll find your error.