Select Distinct DVDTitle, CopyNumber from Actors a
inner join CastMembers b
on a.ActorNumber = b.ActorNumber
inner join DVDTitles c
on b.DVDNumber = c.DVDNumber
inner join DVDCopys d
on c.DVDNumber = d.DVDNumber;
如何在 linq 中撰寫此 sql 查詢：到目前為止，我已經完成了兩次回傳值的操作：
var actorList = from a in _db.Actors
join b in _db.CastMembers
on a.ActorNumber equals b.ActorNumber
join c in _db.DVDTitles
on b.DVDNumber equals c.DVDNumber
join d in _db.DVDCopys
on c.DVDNumber equals d.DVDNumber
orderby c.DvdTitle
select new Actor
{
ActorNumber = a.ActorNumber,
ActorSurName = a.ActorSurName,
ActorFirstName = a.ActorFirstName,
DVDTitle = c.DvdTitle,
CopyNumber = d.CopyNumber
};
我也試過：
var actorList_01 = actorList.Distinct();
但結果是一樣的。
uj5u.com熱心網友回復：
試試這個
var matchingList = actorList
.GroupBy(x => x.ActorNumber )
.Select(g => g.First())
.ToList();
轉載請註明出處，本文鏈接：https://www.uj5u.com/shujuku/465294.html
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