使用LINQ到SQL中的select查询中的值更新

Update TableToBeUpdated
Set ColumnNameId = (Select MasterColumnId 
                    from MasterTable where Id = @Id)
Where ForeingKeyId = @Id
   AND AnotherColumn = @AnotherColumn

如何实现 在上面 有一个select语句和一个update语句吗?

我现在想的是。

  //First Select statement
  var tableTBU = (from t in MsDataContext.TableToBeUpdated 
           where t.ForeingKeyId == <valueFromVariable>
           select t ).SingleOrDefault();

  //Second select statement
  var masterIdValue = (from m in MsDataContext.MasterTable 
                where m.Id == <valueFromVariable>
                select mod.MasterColumnId ).SingleOrDefault();


  tableTBU.ColumnNameId = masterIdValue ;
  tableTBU.SomeOtherColumn = "dkjsdlfs";
  //Some more things to be updated.

  //UpdateStatement
  MsDataContext.SubmitChanges();