Linq distinct&max

Question

我要查询这个表:

symbol    time
------    ----------
aaa       2013-04-18 09:10:28.000    
bbb       2013-04-18 09:10:27.000    
aaa       2013-04-18 09:10:27.000    
bbb       2013-04-18 09:10:26.000

对于具有最大时间值的所有不同符号,我需要一行.我如何编写linq查询？

提前致谢,

Answer 1

通过组行的符号,然后从最高每个组项目选择时间(表是根据上下文数据库表名):

from r in Table
group r by r.symbol into g
select g.OrderByDescending(x => x.time).First()

与方法语法相同:

Table.GroupBy(r => r.symbol)
     .Select(g => g.OrderByDescending(x => x.time).First());

Answer 2

试试这个

var q = MyTable.GroupBy(x => x.symbol )
               .Select(g => g.OrderByDescending(i => i.time).First());

或者像这样使用max

 var data = from r in MyTable
                   group r by r.symbol into g
                   select new { name= g.Key, data= g.Max(a=>a.time) };