How do you do a SQL style 'IN' statement in LINQ to Entities (Entity Framework) if Contains isn't supported?

Question

I\'m using LINQ to Entities (not LINQ to SQL) and I\'m having trouble creating an \'IN\' style query. Here is my query at the moment:

var items = db.InventoryIt         


        

Answer 1

You can use Linq's Any extension method for this in some cases:

var userIds = new[] { 1, 2, 3 };

from u in Users
     where userIds.Any(i => i==u.Id)
     select u;

The generated SQL looks pretty strange in such a case, but like much Linq-to-Entities generated SQL it might be overly verbose for a human, but runs fast in practice.

SELECT 
[Extent1].[Id] AS [Id], 
[Extent1].[DisplayName] AS [DisplayName], 
FROM [dbo].[Users] AS [Extent1]
WHERE  EXISTS (SELECT 
    1 AS [C1]
    FROM  (SELECT 
        [UnionAll1].[C1] AS [C1]
        FROM  (SELECT 
            1 AS [C1]
            FROM  ( SELECT 1 AS X ) AS [SingleRowTable1]
        UNION ALL
            SELECT 
            2 AS [C1]
            FROM  ( SELECT 1 AS X ) AS [SingleRowTable2]) AS [UnionAll1]
    UNION ALL
        SELECT 
        3 AS [C1]
        FROM  ( SELECT 1 AS X ) AS [SingleRowTable3]) AS [UnionAll2]
    WHERE [UnionAll2].[C1] = [Extent1].[Id]
)