[英]The type 'System.Data.Linq.Binary' is not supported in aggregation operations - LINQ
(from chapter in Chapters
join userChapter in UserChapters on chapter.Id equals userChapter.ChapterId
join pub in Publications on chapter.Id equals pub.ChapterId into P
from publication in P.DefaultIfEmpty()
where userChapter.UserId == 9
group new
{
PubID = publication.Id,
Logo = chapter.Logo
} by new { chapter.Id, chapter.Name} into x
orderby x.Key.Name
select new
{
Id = x.Key.Id,
chapterName = x.Key.Name,
PublicationCount = x.Count(z => z.PubID > 0),
Logo = x.Max(z=>z.Logo)
}
)
In the above query " chapter.Logo
" is of type byte[]
, when I try to execute this query i am getting following error. 在上面的查询中,“
chapter.Logo
”的类型为byte[]
,当我尝试执行此查询时,我收到以下错误。
The type 'System.Data.Linq.Binary' is not supported in aggregation operations - LINQ.
LINQ,聚合操作不支持“System.Data.Linq.Binary”类型。
(from chapter in Chapters
join userChapter in UserChapters on chapter.Id equals userChapter.ChapterId
join pub in Publications on chapter.Id equals pub.ChapterId into P
from publication in P.DefaultIfEmpty()
where userChapter.UserId == 9
group new
{
PubID = publication.Id,
Logo = chapter.Logo
} by new { chapter.Id, chapter.Name} into x
orderby x.Key.Name
select new
{
Id = x.Key.Id,
chapterName = x.Key.Name,
Logo = x.Max(z=>z.Logo.Count())
}
) )
(from chapter in Chapters
join userChapter in UserChapters on chapter.Id equals userChapter.ChapterId
join pub in Publications on chapter.Id equals pub.ChapterId into P
from pub in P.DefaultIfEmpty()
where userChapter.UserId == 9
group pub by new { chapter.Id, chapter.Name,chapter.Logo,pub.Id} into x
orderby x.Key.Name
select new
{
Id = x.Key.Id,
chapterName = x.Key.Name,
Logo = x.Key.Logo,
PublicationCount=x.Count()
}
) )
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