LinQ to Entities，Max Date字段，按什么分组

Posted 2021-02-24

from p in PersonOrders
// put your where clause here
group p by p.PersonID into grp //could be grouped by anything, Grouping on Guid ID's is not a good idea
let MaxOrderDatePerPerson = grp.Max ( g=>g.OrderDate )
 
from p in grp
where p.OrderDate == MaxOrderDatePerPerson
select p