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entity object cannot be referenced by multiple instances of IEntityChangeTracker. while adding related objects to entity in Entity Framework 4.1
by CurrentlyPissed in Programming Languages

I am trying to save Employee details, which has references with City. But everytime I try to save my contact, which is validated I get the exception "ADO.Net Entity Framework An entity object cannot be referenced by multiple instances of IEntityChangeTracker"

I had read so many post but still not getting the exact idea of what to do...
my Save button click code is given below

Replacing a child entity in an entity collection that is attached to a parent entity (Master detail scenario)
by postino in Development Tools & Services

I have a Self tracking Entity collection (EF 4) in a silverlight 4 project which is accessed and updated via regular WCF 4 Services (Not RIA). Since I cannot indulge in my real scenario for privacy reasons, here is a very similar scenario.

This is like a Customer/Order/OrderStatus scenario. A customer has a one-to-many relationship with orders. Order has an OrderStatus (set via t

Entity Framework - inserting new entity via objectcontext does not use existing entity properties
by eb. in Web Design

I have an insert method on my repository like so:

public T Insert(T entity)
_ctx.AddObject(EntityName, entity);
return entity;

If I execute the below code, the values assigned to my entity do not propagate to the SQL that is executed.

Category c = new Category();
c.Name = CLEARA

entity framework compare in memory entity to saved entity
by Matt Watson in Programming Languages

I've simplified my code to better illustrate my point. I need to have some business logic where I test if a property has changed from a to b. The problem that I'm facing is that the entity that I am manipulating is attached to my DBContext. If I update the property on one of my references the other is also updated:

var oldEntity = context.Find(x);
var upda

Entity Framework: Update Entity when Another Entity is Updated
by Sigtryggur in Programming Languages

I have an EDM, it includes the entities extension and history. My goal is to use history to keep track of all the changes made to extension entity. For example, if extension with ID 223 has its property 'Name_Display' changed - I want the history entity to record this.

I'm using ASP.NET with VB.NET. Where in my code do I put the hook to say, "update the history entity" and what shou

Entity Framework: Assign entity to property of another entity
by cbot5000 in Coding

I have these entities (this is just an abstraction I created for this post):


These are the references between them:

District * - 1 Language
Description * - 1 Language
District 1 - 1 Description

If I fetch like this:

var myFetch = from c in context.Districts
where c.Id = 10
How to Add existing entity as a new Entity with Entity Framework
by Erenhardt in Programming Languages

I want to create a copy my object in my DB with using Entity Framework

first I got my "Book" from DB

var entity1 = new testEntities();
var book= entity1.Books.First();

then, I tried to add this object as a new object

var entity2 = new testEntities();
book.Id = 0;

doctrine 2, one-to-one association, updates primary key in one entity when adding/deleting related entity
by keyed in Web Design

I have 2 entities
User and Address

User is mapped One to One (Unidirectional) to Address,
both have id/user_id field (primary) which is used for join
with cascade=persist and orphanRemoval=true

when I do
$user = $em->find('ClassesUser',1);

it deletes the address part f

Entity Framework, changing EntityKey leaves Entity as “UnChanged”
by rajnesh in Coding

I have an entity with a status property that I would like to update.

I would like to do the following:

const int NEW_STATUS = 2;
myEntity.StatusReference.EntityKey = new EntityKey("SetName", "KeyName", NEW_STATUS);

When this is passed to the context, its state is "UnChanged", despite me changing the relationship! This means the save will not

Entity Framework and WCF Data Services : Calling business logic after persisting entity
by Riparian in Coding

We have an Entity Data Model which is used by a WCF Data Service that needs to run some business logic after persisting an entity to the database. In this case it needs to pass the id generated for the persisted entity to another service via a WCF web service call.

The question is how do we run some business logic after saving the entity. Part of this business logic will be a call


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