ขอสอบถามเกี่ยวกับ Linq Join 2 Datatable โดยใส่เงื่อนไข ครับ

var query =  from c in ExceptResult
where !( from o in dtResult select o.ID).Contains( c.ID )
select c;

var query = from d1 in dt1.AsEnumerable()
   join d2 in dt2.AsEnumerable() on d1.Field<int>("ID") == d2.Field<int>("ID") && 
   d1.Field<TimeSpan>("time") == d2.Field<TimeSpan>("time") into jd2
   from j2 in jd2.DefaultIfEmpty()
   where j2 == null
   select d1;