public virtual void DateDiffYear()
{
DateTime dt = new DateTime(1997, 8, 25);
DateTime dt1 = new DateTime(1996, 9, 15);
var expected = dt.Year - dt1.Year;
var actual = db.Orders.Select(o => o.OrderDate == dt && SqlMethods.DateDiffYear(o.OrderDate, dt1) == expected).FirstOrDefault();
Assert.IsNotNull(actual);
var item = db.Orders.Where(o => o.OrderDate == dt && SqlMethods.DateDiffYear(dt1, o.OrderDate) == expected).FirstOrDefault();
Assert.IsNotNull(item);
}