LINQ where子句不返回结果

Question

当我使用Where子句（LINQ）时，结果集返回空，我收到错误“枚举没有产生结果”。可能有什么问题？

public class Stores
{
    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int StoreId { get; set; }
    public string StoreName { get; set; }
    public string Address { get; set; }
    public string Telephone { get; set; }
    public int TownId { get; set; }
}

public DbSet<Stores> Store { get; set; }

var storeList = from n in db.Store
                where n.TownId == 10
                select n;