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EF Foreign Key Associations Deleted

The picture show relation with two tables in my database;
Well as you can see there's a field called "DeviceTypeID" in the right side table.
Normally EF adds CompanyTypeID column to the ServiceLaburDefinitions model but it's disappeared last time I updated model from the database.
I am searching for a solution for a couple of hours but not able to find any solution. Could anyne suggest a solution?
Thanks.

ServiceLaburDefinitions is the depend entity and has the DeviceTypeID foreign key property defined.
So Entity Framework creates a navigation Key under the hood between the 2 tables based on DeviceTypeId key.
You can see for example how a navigation key is created also in the following example between the foreign key and the primary key
More information about navigation properties can be found here
When you create the model from the database, there is a checkbox marked "Include Foreign Key columns In The Model" - Make sure this is checked.

EF6 Table Splitting with foreign keys (Database first)

I'm currently investigating the possibility to use table splitting with EF to stop pulling too many columns for nothing. As for now, I'm able to create a new entity, cut/paste the fields into the sub-entity and map it without much problems.
However, if one of those fields is a FK in the master table, it gives me the following error
"Running transformation: There is no property with name 'IdDocumentImportSource' defined in type referred by Role 'DocumentImports'."
I do understand that the both tables have a NavigationProperties that cannot be resolved anymore by the association FK because the field has been moved to the child table.
Here's my question; Is there a way to automaticaly move the association FK to the child table? I could only make it work by manually deleting the association, both navigation properties, creation the association FK of the child. It involves quite a lot of work on my part if I have to do all this manually for every association FK I got...!
DocumentImports is the ParentTable that I splitted into a new child table DocumentImports_StatusDetail and DocumentImportSources is the table being referenced by the FK.
Thanks!

Create a pseudo foreign key on a view using entity framework

I have created a view "Supplier" that shows columns from a table "T_ADDRESS". The view is declared as (I know, the '*' is a no-go in views)
create View Supplier as
select * from T_ADRESSEN where IsSupplier = 1
In EF, I want to use the view as it is more readable than the ugly "T_ADRESSEN". So far so easy.
Now comes the tricky part (for me). The table T_ADDRESS has a self referencing foreign key "MainAddressId" which points to T_ADDRESS.
Creating a DB-first (or CodeFirst from DB) will create the FK relationship for the table T_ADDRESS (and the navigational properties), but not for the view 'Supplier'. Of course not: EF does not know anything about the FK relationship (although the view exposes the same columns).
Now I tried to use the 'ForeignKey' and 'InverseProperty' attributes in my code first model on the Supplier-class but this gives me an ModelValidationException. Also clear: There is no such FK-relationship.
How can I tell EF to treat a field just like a foreign key although the constraint does not exist?
What I am trying to do is to have 'Suppliers' in my EF model (as a subset of T_ADDRESS). If there is another way to do it, I would be happy to receive a hint.

You can't define ForeignKey and InverseProperty on a view. In your case, you need to use that ugly T_ADRESSEN table and use [AutoMapper][1] to map it the to the DTO class. In your case, T_ADRESSEN is the context table and Supplier is your DTO class.
with AutoMapper you can do something like this:
var ugly = context.T_ADRESSEN.Where(e=>e.IsSupplier ==1);
var suppliers = mapper.Map<IEnumerable<Supplier>>(ugly);
where mapper is IMapper interface defined in AutoMapper.
Sometime one should figure out that the DTO mapping technique as a replacement to the traditional database view.

How to get parent entity key?

I use EntityFramework and in my edmx file I have two tables mapped:
Customers
column:
Id PK
and Orders
columns:
Id PK
CustomerId FK
which are associated.
When I take Order object there IS Customer property but I can't see CustomerId property.
I used to work with L2SQL and I expected to see CustomerId but EF somehow hides it.

the Add Association dialog in the EF edmx designer allows you to specify (via a checkbox) whether or not you want to have a "Foreign Key" (and/or a Navigation Property) created for the association. did you make sure it's checked?

Inside the Customer property, there should be a CustomerId property.
So try..
myOrderObject.Customer.CustomerId

How exactly is the id column in the order table named? Usually the EF-Designer should create a property for each column in the database table. Have a look at the "Mapping details" page (which you can open in the context menu of the EF designer) to see if (and to which property) the column is mapped.

Problems with automatic property creation when manually mapping relationships between tables with no foreign keys in L2S

Pardon the massive headline.
I'm in the situation of having to build an application on top of a database, that I cannot make any changes to. The database does not have any primary- or foreignkeys set.
I'm using linq-2-sql, and I'm interested in having some properties exposed on the entities generated from my dbml. For instance, in the hypothetical example of a one-to-many relationship between table education and student - where each student record has a reference to an education id, I'd like to be able to go:
var student = GetAStudentFromContextOrWhatever();
var studentsEducation = student.Education;
It is my experience, that this kind of property is automatically generated when I drag'n'drop tables with foreignkey relationships from the server explorer.
However as previously mentioned, in this case I do not have these foreign key relationships - rather I am adding the relationships manually in the dbml file, specifying parent and child class.
When I add these relationships, I expect the involved entities in the designer.cs of my context to get populated with properties of a kind like those described above.
This, however, does not happen.
What must I do for my dbml to create these properties for me - based on these manually mapped associations between entities/tables that, on a database level, do not have foreign key associations?
Cheers!

L2S is just that Linq-to-SQL. If it isn't in SQL it won't be generated. The expression trees behind L2S just can't understand what you are doing. The place for your association is in a partial class file which you will have create manually. Also it probably won't update or insert through the association.

I know this is a very old question, but I just ran into the same problem. In order for the relationship in the DBML designer to automatically create the association properties for you, you need to have primary keys on your objects. If you click the column name in the designer, you'll see that your PK field has PrimaryKey = false. Switch that to True and build; all should be well.
Patrick