如何在 LINQ 查询中执行此聚合、分组依据？
请不要给我一个完整的工作示例，我想知道这是如何完成的，而不是获取一些可以复制粘贴的代码
这是我需要的查询，但不能用于我在 LINQ 中创建它。
SELECT * FROM
dbo.Schedules s, dbo.Videos v
WHERE s.VideoID = v.ID
AND s.ID IN
(
SELECT MAX(ID) FROM dbo.Schedules
WHERE ChannelID = 1
GROUP BY VideoID
)
ORDER BY v.Rating DESC, s.StartTime DESC
我在 LINQ 中有“IN”查询，我认为，它是这样的，
var uniqueList = from schedule in db.Schedules
where schedule.ChannelID == channelID
group schedule by schedule.VideoID into s
select new
{
id = s.Max(i => i.ID)
};
这可能是错误的，但现在我无法在 where 子句中检查另一个查询 uniqueList.Contains(schedule.ID)
可能有更好的方法来编写此查询，如果您有任何想法，我会喜欢一些提示。
我收到此错误，但它没有多大意义。
无法从用法中推断出方法“System.Linq.Queryable.Contains(System.Linq.IQueryable, TSource)”的类型参数。尝试显式指定类型参数。
Please do not give me a full working example, I want to know how this is done rather than to get some code I can copy paste
This is the query I need, and can't for the life of me create it in LINQ.
SELECT * FROM
dbo.Schedules s, dbo.Videos v
WHERE s.VideoID = v.ID
AND s.ID IN
(
SELECT MAX(ID) FROM dbo.Schedules
WHERE ChannelID = 1
GROUP BY VideoID
)
ORDER BY v.Rating DESC, s.StartTime DESC
I have the "IN" query in LINQ I think, it's something like this
var uniqueList = from schedule in db.Schedules
where schedule.ChannelID == channelID
group schedule by schedule.VideoID into s
select new
{
id = s.Max(i => i.ID)
};
It is possibly wrong, but now I can not check in another query for this in a where clause uniqueList.Contains(schedule.ID)
There is possibly a better way to write this query, if you have any idea I would love some hints.
I get this error and it's not making much sense.
The type arguments for method 'System.Linq.Queryable.Contains(System.Linq.IQueryable, TSource)' cannot be inferred from the usage. Try specifying the type arguments explicitly.
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尝试使用 .Where(sInner=> s.ID == sInner.ID).Any()。
我只能在具有简单列表的 linq 表达式中使用 .Contains 。尽管您发布的内容似乎是编译时错误，但一旦您解决了它，我认为您最终会遇到像我过去一样的运行时错误。
try with .Where(sInner=> s.ID == sInner.ID).Any().
I have only been able to use .Contains in linq expressions with simple lists. Although what you posted seems to be a compile time error, once you get around it I think you'll end up getting a runtime error like I have in the past.