In entity framework there was a known issues or views with no primary will returns all the duplicated rows, because it couldn’t identity what’s different in the rows without a primary key.
There is a quick code fix we can apply to that,
Instead of using context.viewTest.toList(), we use the following:
In EF 5:
context.Database.SQLQuery<viewTest>(“Select * from viewTest”);
In EF 4:
context.ExecuteStoreQuery<viewTest>(“Select * from viewTest”);