public class Products
{

    [Required]
    public long Id { get; set; }
    public long UserId { get; set; }
    public long OwnerId { get; set; }
    [ForeignKey("OwnerId")]
    public Users Owner { get; set; }
    [ForeignKey("UserId")]
    public Users User { get; set; }
    public string Title { get; set; }
    public string ShortDescription { get; set; }
    public string LongDescription { get; set; }
    [Required]
    public DateTime Date { get; set; }
    public decimal Price { get; set; }
    [Column("Picture1", TypeName = "image")]
    public byte[] Picture1 { get; set; }
    [Column("Picture2", TypeName = "image")]
    public byte[] Picture2 { get; set; }
    [Column("Picture3", TypeName = "image")]
    public byte[] Picture3 { get; set; }
    public int State { get; set; }
}

public class Users
{
    public long Id { get; set; }
    [Required]
    public string FirstName { get; set; }
    [Required]
    public string LastName { get; set; }
    [Required]
    public DateTime BirthDate { get; set; }
    [Required]
    public string Email { get; set; }
    [Required]
    public string UserName { get; set; }
    [Required]
    public string Password { get; set; }
}

public class SiteDBContext : DbContext
{
    public SiteDBContext()
        : base("name =SiteDBContext")
    {

    }

    public DbSet<Users> Users { get; set; }
    public DbSet<Products> Products { get; set; }
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
    }
}