Linq TO EF 联合查询JOIN简单示例

var result = ef.M_Record.Where(where).GroupBy(g => new { g.F_FireID})
.Select(s => new { MR_ID =s.Max(m=>m.MR_ID)})
.Join(ef.M_Record,
L => E.MR_ID,
R => F.MR_ID, (L, R) => new
{
F_FireID = R.F_FireID,
MR_ID = R.MR_ID,
MR_Type = R.MR_Type,
}).OrderByDescending(o => o.MR_ID).ToList();