public class CompanyAdmin
{
    public string Id { get; set; }
    [Required(AllowEmptyStrings = false)]
    [Display(Name = "Company Name")]
    public string CompanyName { get; set; }
    public virtual List<Certificate> Certificates { get; set; }


public class Certificate
{
    [Key]
    [Display(Name = "Certificate No.")]
    public string CertNo { get; set; }
    [Display(Name = "Company")]
    public IEnumerable<SelectListItem> Companies { get; set; }
    [Required]
    public string Company { get; set; }
    [Display(Name = "User")]
    public IEnumerable<SelectListItem> UserList { get; set; }
    [Required]
    public string User { get; set; }
    public string UploadedBy { get; set; }
    [Display(Name = "Description")]
    public string CertDescription { get; set; }
    [Display(Name = "File Location")]
    public string CertFileLocation { get; set; }
    [Display(Name = "Last Modified")]
    public DateTime LastModifiedDate { get; set; }

}

public class CertificateViewModel
{
    [Display(Name = "Certificate No.")]
    public string CertNo { get; set; }
    public string User { get; set; }
    [Display(Name = "User")]
    public string UserName { get; set; }
    public string Company { get; set; }
    [Display(Name = "Company")]
    public string CompanyName { get; set; }
    [Display(Name = "Description")]
    public string CertDescription { get; set; }
    [Display(Name = "Last Modified")]
    public DateTime LastModifiedDate { get; set; }
 }

public ActionResult Index()
    {
        if (User.IsInRole("Admin"))
        {
            IEnumerable<CertificateViewModel> model = null;

            model = (from c in db.CertificateDB
                     join u in db.Users on c.User equals u.Id
                     join d in db.CompanyDB on c.Company equals d.Id
                     select new CertificateViewModel
                     {
                         CertNo = c.CertNo,
                         UserName = u.UserName,
                         CompanyName = d.CompanyName,
                         CertDescription = c.CertDescription,
                         LastModifiedDate = c.LastModifiedDate
                     }
                );
            return View(model);
        }
        else
        {
            return RedirectToAction("Index", "Home");
        }

    }

@model IEnumerable<IdentitySample.Models.CertificateViewModel>
<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.CertNo)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.Company)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.User)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.CertDescription)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.LastModifiedDate)
        </th>
        <th></th>
    </tr>

    @foreach (var item in Model)
    {
        <tr>
            <td>
                @Html.DisplayFor(modelItem => item.CertNo)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.Company)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.User)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.CertDescription)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.LastModifiedDate)
            </td>
            <td>
                @Html.ActionLink("Edit", "Edit", new { id = item.CertNo }) |
                @Html.ActionLink("Details", "Details", new { id = item.CertNo }) |
                @Html.ActionLink("Delete", "Delete", new { id = item.CertNo })
            </td>
        </tr>
    }

</table>

public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
    public ApplicationDbContext()
        : base("DefaultConnection", throwIfV1Schema: false)
    {
    }

    static ApplicationDbContext()
    {
        // Set the database intializer which is run once during application start
        // This seeds the database with admin user credentials and admin role

        Database.SetInitializer<ApplicationDbContext>(new ApplicationDbInitializer());
    }

    public override int SaveChanges()
    {
        try
        {
            return base.SaveChanges();
        }
        catch (DbEntityValidationException ex)
        {
            string errorMessages = string.Join("; ", ex.EntityValidationErrors.SelectMany(x => x.ValidationErrors).Select(x => x.PropertyName + ": " + x.ErrorMessage));
            throw new DbEntityValidationException(errorMessages);
        }
    }

    public DbSet<CompanyAdmin> CompanyDB { get; set; }
    public DbSet<Certificate> CertificateDB { get; set; }

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }
}