static void Main() { using (NorthwindEntities northwindEnteties = new NorthwindEntities()) { var person = northwindEnteties.Employees.FirstOrDefault(e => e.EmployeeID == 11); person.FirstName = "AAAAA"; northwindEnteties.SaveChanges(); } using (SecondContext.SecondContextEntities northwindEnteties2 = new SecondContext.SecondContextEntities()) { var person = northwindEnteties2.Employees.FirstOrDefault(e => e.EmployeeID == 11); person.FirstName = "DDDD"; northwindEnteties2.SaveChanges(); } }