linq to sql 查询有关问题 _Web开发

linq to sql 查询问题
我的查询语句：
DateTime dt = new DateTime(1900, 1, 1);
var list = (from p in resarchData
join t in times
on p.workCls equals t.WorkCls into g
from r in g.DefaultIfEmpty(new CPM_PJ_PLAN_TIME { ID = 0,PJ_TIME_EDATE = dt, PJ_TIME_SDATE = dt })
select new
{
code = p.code,
workCls = p.workCls,
Item = p.Item,
sDate = r.PJ_TIME_SDATE,
eDate = r.PJ_TIME_EDATE,
comment = r.PJ_TIME_COMMENT,
pid = r.Pid
}

);
t表中有时间就显示，如果没有就不管，repeate绑定的时候就是空白，但是我的查询我给了个默认时间，呈现出来的全是默认时间，没有查出数据库t表的值，如果不给默认的怎么能得到我想要的结果呢？

------解决方案--------------------

C# code

 DateTime dt = new DateTime(1900, 1, 1);
  var list = (from p in resarchData
  join t in times
  on p.workCls equals t.WorkCls into g
  from r in g.DefaultIfEmpty()
  select new
  {
  code = p.code,
  workCls = p.workCls,
  Item = p.Item,
  sDate =r==null?dt : r.PJ_TIME_SDATE,
  eDate = r==null?dt:r.PJ_TIME_EDATE,
  comment = r==null?"":r.PJ_TIME_COMMENT,
  pid = r==null?"":r.Pid
  }

  );

------解决方案--------------------
有专门的LINQ版块的:
http://forum.csdn.net/SList/LINQ/