[RESOLVED] MVC5 Code-First Database Schema

[BrailleSchool]

Two things, I am new to MVC and need to confirm if this looks right. Also I am told by the IDE that a public string is not nullable. The database would have a nullable varchar type.

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Web;
 
namespace NotaryNet.Models
{
    /// <summary>
    /// Registration Database Structure.
    /// </summary>
    /// <remarks>
    /// 1. Company name during registration must be unique. Not allow same company name to be registered.
    /// 2. Initial registered user is automatically assigned to the Admin Role and they can register/create additional users as needed.
    ///     A. If any additional user accounts are created by the Admin, they will be added to the Users role.
    /// 3. Each SystemUser has their own respective information about them in the SystemUsersInfo table.
    /// 
    /// 1. Company and SystemUsers share a PK (CompanyID) and FK (CompanyID) relationship.
    /// 2. SystemUsers and SystemUsersInfo share a PK (UserID) and FK (UserID) relationship.
    /// </remarks>
 
    [Table("Companies")]
    public class Register
    {
        [Key]
        public int CompanyID { get; set; }
        public string CompanyName { get; set; }
        public bool IsActive { get; set; }
        public virtual ICollection<SystemUsers> SystemUsers { get; set; }
    }
 
    [Table("SystemUsers")]
    public class SystemUsers 
    {
        [Key]
        public int UserID { get; set; }
        public string Username { get; set; }
        public string Password { get; set; }
        public bool IsActive { get; set; }
        [ForeignKey("CompanyID")]
        public virtual ICollection<SystemUserInfo> SystemUserInfo { get; set; }        
    }
 
    [Table("SystemUserInfo")]
    public class SystemUserInfo
    {
        [Key]
        public int SystemUserInfoID { get; set; }
        public string NamePrefix { get; set; }
        public string FirstName { get; set; }
        public string? MiddleInitial { get; set; }
        public string LastName { get; set; }
        public string? NameSuffix { get; set; }
        [ForeignKey("UseID")]
    }
}