Entity Framework doesn't update Many to Many relation

Hi Experts,

I have the following tables in an SQL2008 database:

Accommodation

code	varchar(18)
name	varchar(80)

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This table has more columns but i have removed them here for simplicity.

Attributes

code	int
name	varchar(50)

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AccommodationAttributes

AccommodationCode	varchar(18)
AttributeCode	int

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As you may get, AccommodationAttributes describes the many to many relationship between Accommodations and Attributes.

I have created my model (EF5) using database first, and it has created two classes linked with a navigation property.

All this seems correct.

What i am trying to do is add values in the db, but though i am able to add Accommodations and Attributes, i don't seem to be able to make it add the corresponding values in the AccommodationAttributes table.

I am reading from an XML file.
Bellow is a code sample of what i am trying to do.

var Accommodations = from a in xe.Elements("accommodation") select a;
foreach (var accommodation in Accommodations)
{
   var AccCode = accommodation.Element("code").Value;
   Accommodation a = context.Accommodations.Where(x=>x.code == AccCode).SingleOrDefault();
   bool newAccommodation = a == null ? true : false;
   a = !newAccommodation ? a :
      new Accommodation
      {
          code = accommodation.Element("code") == null ? null : accommodation.Element("code").Value,
          name = accommodation.Element("name") == null ? null : accommodation.Element("name").Value
      };
      foreach (var attribute in accommodation.Elements("attributes").Elements("attribute").Select(x=>x.Value))
      {
         Attribute at = context.Attributes.Where(x => x.name == attribute).SingleOrDefault();
         a.Attributes.Add(at);
      }
      context.SaveChanges();
}

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After running this code i Run the following in SQL:

select COUNT(*) from Accommodations
select COUNT(*)from Attributes
select COUNT(*)from AccommodationAttributes

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But though i see entries in the two tables, the link table comes with 0 rows.

I have tried other variations, like attaching the objects to the context, or implicitly specifying that it is a modified object.

By the time that this code will run i am sure that the Attributes are allready inserted in the db, but the Accommodation is either an Insert or Update.

I am eager to hear your thoughts,

Giannis