How to do a Bulk Insert -- Linq to Entities
Solution 1:
Sometimes you simply have to mix models. Perhaps use SqlBulkCopy for this part of your repository (since this plugs directly into the bulk-copy API), and Entity Framework for some of the rest. And if necessary, a bit of direct ADO.NET. Ultimately the goal is to get the job done.
Solution 2:
For a perfect example of how to do bulk inserts with LINQ to Entities, see http://archive.msdn.microsoft.com/LinqEntityDataReader. It is a wrapper that allows easy use of SqlBulkCopy.
@Marc Gravell is correct, sometimes you have to mix models to get the job done.