add user database links

University/DatabaseImplement/Models/Student.cs

@@ -17,6 +17,8 @@ namespace UniversityDatabaseImplement.Models
         public virtual List<StatementStudent> StatementStudents { get; set; } = new();
         [ForeignKey("StudentId")]
         public virtual List<StudentExaminationResult> StudentExaminationResults { get; set; } = new();
+        [ForeignKey("StudentId")]
+        public virtual List<UserStudent> StudentUsers { get; set; } = new();
 
         private Dictionary<int, IStatementModel>? _statements;
         [NotMapped]

University/DatabaseImplement/Models/User.cs

@@ -21,6 +21,10 @@ namespace UniversityDatabaseImplement.Models
         public string Login { get; set; } = string.Empty;
         [Required]
         public string Password { get; set; } = string.Empty;
+        [ForeignKey("UserId")]
+        public virtual List<UserStudent> StudentUsers { get; set; } = new();
+        [ForeignKey("UserId")]
+        public virtual List<Statement> Statements { get; set; } = new();
         public static User Create(UserBindingModel model)
         {
             return new User

University/DatabaseImplement/Models/UserStudent.cs

@@ -0,0 +1,15 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace UniversityDatabaseImplement.Models
+{
+    public class UserStudent
+    {
+        public int Id { get; set; }
+        [Required]
+        public int StudentTypeId { get; set; }
+        [Required]
+        public int UserId { get; set; }
+        public virtual Student Student { get; set; } = new();
+        public virtual User User { get; set; } = new();
+    }
+}

University/DatabaseImplement/UniversityDatabase.cs

@@ -24,5 +24,6 @@ namespace UniversityDatabaseImplement
         public virtual DbSet<Student> Students { set; get; }
         public virtual DbSet<StudentExaminationResult> StudentExaminationResults { set; get; }
         public virtual DbSet<User> Users { set; get; }
+        public virtual DbSet<UserStudent> UserStudents { set; get; }
     }
 }