One to one issue (add 2 child)

[orit1]

hi,

I have 3 tables:

1. Activity
2. ACT_Activity
3. ActivityToEntity
   All table have a PK named ID
   the PKs of Activity and ActivityToEntity are defined Auto Generate in DB
   the relation betweeen Activity and ACT_Activity is one to one
   by Activity.ID(PK) and ACT_Activity.ID(PK)
   the relation betweeen Activity and ActivityToEntity is one to many
   by Activity.ID(PK) and ActivityToEntity .ActivityID(FK)

I select from DB Activity, add 2 ActivityToEntity and save and all is well
but if I select Activity and load ACT_Activity
like that:
context.Entry(activity1).Reference(a => a.ACT_Activity).Load();
add 2 ActivityToEntity and save
I get the following error:
in TrackableEntities.EF6. DbContextExtensions in function: SetEntityState at line:
context.Entry(item).State = state;

Attaching an entity of type 'TrackableGettingStarted.Entities.Shared.Net45.ActivityToEntity' failed because another entity of the same type already has the same primary key value. This can happen when using the 'Attach' method or setting the state of an entity to 'Unchanged' or 'Modified' if any entities in the graph have conflicting key values. This may be because some entities are new and have not yet received database-generated key values. In this case use the 'Add' method or the 'Added' entity state to track the graph and then set the state of non-new entities to 'Unchanged' or 'Modified' as appropriate.

if I add one ActivityToEntity all is good again

What do I need to change so I can add 2 ActivityToEntity?

Thanks in advance!

[tonysneed]

Can you try setting their TrackingState to Added?

[orit1]

it's already in Added TrackingState

[orit1]

the error appears when entity is ACT_Activity
before it cames to the ActivityToEntity child
at line:
context.Entry(item).State = state;

[orit1]

if I change the entity framework state for child (ActivityToEntity) before ApplyChanges()
that like:
context.Entry(activity.ActivityToEntity[0]).State = EntityState.Added;
context.Entry(activity.ActivityToEntity[1]).State = EntityState.Added;
all is good

so I think that the problem is that when I entry first time to set ACT_activity state I already have 2 child in Activity object and they both without entity framework state Added (deAttach)
Even though TrackingState is Added but is not relevant for entity framework

It is a normal behavior and I do something worng or it is a something that need to be fix?