public void SubQueryWithGT_LT() { CustomerCollection coll = new CustomerCollection(); coll.es.Connection.ConnectionString = UnitTestBase.GetFktString(coll.es.Connection); switch (coll.es.Connection.ProviderSignature.DataProviderName) { case "EntitySpaces.SqlServerCeProvider": case "EntitySpaces.SqlServerCe4Provider": Assert.Ignore("Not supported."); break; default: DateTime fromDate = new DateTime(2005, 1, 1); DateTime toDate = new DateTime(2005, 8, 31); DateTime startDate = new DateTime(2000, 1, 1); DateTime endDate = new DateTime(2000, 12, 31); CustomerQuery cq = new CustomerQuery("c"); OrderQuery oq = new OrderQuery("o"); OrderQuery oqSub = new OrderQuery("oSub"); oqSub.Select(oqSub.OrderDate.Max()); oqSub.Where(oqSub.CustID == cq.CustomerID & oqSub.CustSub == cq.CustomerSub); // These work in SubQuery oqSub.Where(oqSub.OrderDate >= fromDate); oqSub.Where(oqSub.OrderDate <= toDate); // If you comment the above 2 GT/LT lines // and un-comment the Between line below // it gets Null Reference exception on Load() //oqSub.Where(oqSub.OrderDate.Between(fromDate, toDate)); cq.es.Distinct = true; cq.Select(cq.CustomerID, cq.CustomerSub, cq.DateAdded, oqSub.As("MaxOrderDate")); cq.InnerJoin(oq).On(cq.CustomerID == oq.CustID & cq.CustomerSub == oq.CustSub); // This works in outer query cq.Where(cq.DateAdded.Between(startDate, endDate)); Assert.IsTrue(coll.Load(cq)); Assert.AreEqual(1, coll.Count); break; } }