EF Find entities not in list - asp.net-mvc

Question

I have this entities:
Product
public class Product
{
public int Id { get; set; }
public string Name { get; set; }
}
PriceList
public class PriceList
{
public int Id { get; set; }
public string Name { get;set; }
}
PriceListProduct
public class PriceListProduct
{
public int Id { get; set; }
public int PriceListId { get; set; }
public int ProductId { get; set; }
public virtual Product Product { get; set; }
}
Question is, how can I get the products not in Price List using LINQ?
My first thought was the use of Contains, but the list of products could be greater than 100000, if Contains is translate as a query like WHERE NOT IN clause, SQL has an approximate limit of 2000 parameters, so besides performance, I think this is not the best approach.
Is there another way? Should I use raw queries?
Update # 1
I'm trying to understand GroupJoin following #Indregaard answer. So far I have this.
var productsWithNoPrice = db.Product()
.GroupJoin(db.PriceListProduct().Where(plp => plp.PriceListId == 2)
.Select(plp => plp.Product),
p => p.Id,
plp => plp.Id,
(p, product) => new { p.Id, Product = product })
.Where(p => !p.Product.Any())
.Select(p => p.Product);
With the filter
.Where(plp => plp.PriceListId == 2)
I'm filtering products from Price List with Id 2. I think this is close but the query generated by SQL returns a number of rows that corresponding to the number of products that not exists in the Price List but every single column is null.
Basically what I need is a query like this
select * from Product p
left join PriceListProduct plp on plp.ProductId = p.Id and plp.PriceListId = 2
where plp.Id is null

Answer 1

So you are looking for Antijoin.
Manual approach could be like this:
var query =
from p in db.Products
join plp in db.PriceListProducts
on p.Id equals plp.ProductId into priceLists
where !priceLists.Any()
select p;
Another way:
var query = db.Products
.Where(p => !db.PriceListProducts.Any(plp => p.Id == plp.ProductId));
But the best way is to create all navigation properties in the model
public class Product
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<PriceListProduct> PriceLists { get; set; }
}
and let EF create queries for you
var query = db.Products.Where(p => !p.PriceLists.Any());

Answer 2

Have you tried Join/GroupJoin?
I haven't tried against a database to see if the generated sql is valid/working but against regular objects something like this will work.
var productsWithNoPrices = products.GroupJoin(productPriceList,
product => product.Id,
productprice => productprice.ProductId,
(product, productPrice) => new { Product = product, Prices = productPrice})
.Where(c=>!c.Prices.Any()).Select(c=>c.Product);
Edit: Based on your updated question I think you want something like this:
var productsWithNoPrices = db.Products.GroupJoin(db.PriceListProducts.Where(c => c.PriceListId == 2),
product => product.Id,
productprice => productprice.ProductId,
(product, productPrice) => new { Product = product, Prices = productPrice }).Where(c=>!c.Prices.Any()).Select(c=>c.Product);
GroupJoin will take whats in your left table (db.Products), join with whats in your right table (db.PriceListProducts.xxxxx) (parameter 1): each product from the left table will get a list of matches from right, combined on product ids (param 2 and 3), output to a anonymous type (param 4). Filter all this on where there is no productprice and select the products. This results in the following SQL, which seems to give the desired result?
SELECT
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name]
FROM [dbo].[Products] AS [Extent1]
WHERE NOT EXISTS (SELECT
1 AS [C1]
FROM [dbo].[PriceListProducts] AS [Extent2]
WHERE (2 = [Extent2].[PriceListId]) AND ([Extent1].[Id] = [Extent2].[ProductId])
)