Entity framework 4 with ctp5 and dirty generated sql

Question

I have a problem with strange generated SQL in ef4 ctp5.

I have simple model with mapping :

[Table("post_auction")]
public class PostAuction
{
    [Key,Column(Name="Id"),DatabaseGenerated(System.ComponentModel.DataAnnotations.DatabaseGenerationOption.Identity)]
    public int Id { get; set; }

    [Column(Name = "Number")]
    public int Number { get; set; }

    [Column(Name = "Label")]
    public string Label { get; set; }

    [Column(Name = "Description")]
    public string Description { get; set; }

    [Column(Name = "CategoryId")]
    public int PostAuctionCategoryId { get; set; }

    [Column(Name = "PriceCZK")]
    public int PriceCZK { get; set; }

    [NotMapped]
    public bool IsAuctionPhotoExitst
    {
        get
        {
            if (File.Exists(HttpContext.Current.Server.MapPath("~/Public/Images/Posts/Thumbs/small_" + this.Number + ".jpg")))
                return true;
            return false;
        }
    }
}

and my linq query is :

_rovastampDbContext.PostAuctions.Where(x => x.PostAuctionCategoryId == auctionId).OrderBy(x => x.Id).ToList();

Ef4 profiler shows me

SELECT   
    [Project1].[Id]          AS [Id],
    [Project1].[Number]      AS [Number],
    [Project1].[Label]       AS [Label],
    [Project1].[Description] AS [Description],
    [Project1].[CategoryId]  AS [CategoryId],
    [Project1].[PriceCZK]    AS [PriceCZK]
FROM
    (SELECT 
         [Extent1].[Id]          AS [Id],
         [Extent1].[Number]      AS [Number],
         [Extent1].[Label]       AS [Label],
         [Extent1].[Description] AS [Description],
         [Extent1].[CategoryId]  AS [CategoryId],
         [Extent1].[PriceCZK]    AS [PriceCZK]
     FROM   
         [dbo].[post_auction] AS [Extent1]
     WHERE  
         [Extent1].[CategoryId] = 1 /* @p__linq__0 */) AS [Project1]
     ORDER BY 
         [Project1].[Id] ASC

My question is a pretty simple : Why ef4 generate that complicated query, when right one is

SELECT ... 
FROM TABLE 
WHERE CategoryId = 1 
ORDER BY Id ASC

Thanks for your advice :)

Martin

EDIT : If I let EF to create db automatic, the problem with query persists...

Answer 1

Excellent question. I'm guessing that it's a bug, since my (edmx-generated) Entity Framework context doesn't produce a projection the way yours does. I would report it as a bug.