Fetch data using LINQ query with left join and AsExpandable() - linq

Question

I have following two tables: Images and Articles
Both the tables are linked by the ImageId column.
An image can be associated with multiple articles.
For example: Images table has 100 rows and Articles table has 200 rows.
Out of these 100 images assume that only 90 are used across the Articles. In this case some of the images are repeated across many articles.
Here I want to fetch the unused 10 images (from Images table) and also want to include the ones that are associated with articles not more than 2 times. I want to ignore those images which are associated with the articles more than 2 times.
I tried the below linq query but it is not working for me.
var predicate = PredicateBuilder.True<Image>();
if (type != null && type != 0)
{
predicate = predicate.And(c => c.ImageType == type);
}
if (!string.IsNullOrWhiteSpace(keyword))
{
predicate = predicate.And(c => c.Name.Contains(keyword) || c.Keyword.Contains(keyword));
}
int skip = numberofImages * (page - 1);
var images = (from imgs in context.Images
join art in context.Articles on imgs.ImageId equals art.ImageId into unusedImages
from img in unusedImages.DefaultIfEmpty()
group img by imgs.ImageId into grouped
.AsExpandable()
.Where(predicate)
orderby Guid.NewGuid(), imgs.ImageId descending
select imgs)
.Skip(skip).Take(numberofImages).ToList();
Can any one help me to fix this issue?

Answer 1

split your query something like this,i wont complicate what is preferably simple
var usedArticles = (from item in context.Articles
group item by imageid into newList
select new
{
imageid = newList.key,
count =newlist.count
}).ToList();
var unwaantedImageIds = usedArticles.where(x=>x.count>2).Select(y=>y.imageId).ToArray();
var unwantedImages =context.image.where(x=>unwaantedImageIds.contains(x.imageId));
var result = context.images.Except(unwaantedImageIds).ToList();