EF-Linq

一丶基本语法
(from a in Table where a.id="001" select a).Tolist();

隐式内连接
from a in table1 join b in table2 on a.id equals b.id select new {
a.id,b.id
}
隐式外连接
from a in table1 from b in table2 where a.id==b.id select new {}
左外连接
from a in table1 join b in table2 on a.id equals b.id into xx from c in xx.DefaultIfEmpty()
select new {

}

group by into 分组
(from u in table1 group u by u.Sex into xx select xx).Tolist