diff --git a/.vs/StudyLib/DesignTimeBuild/.dtbcache.v2 b/.vs/StudyLib/DesignTimeBuild/.dtbcache.v2
index 58a4633..640dd35 100644
Binary files a/.vs/StudyLib/DesignTimeBuild/.dtbcache.v2 and b/.vs/StudyLib/DesignTimeBuild/.dtbcache.v2 differ
diff --git a/.vs/StudyLib/v16/.suo b/.vs/StudyLib/v16/.suo
index 9214c04..5773998 100644
Binary files a/.vs/StudyLib/v16/.suo and b/.vs/StudyLib/v16/.suo differ
diff --git a/API/Controllers/GroupCandidatesController.cs b/API/Controllers/GroupCandidatesController.cs
index 583a48e..46134a7 100644
--- a/API/Controllers/GroupCandidatesController.cs
+++ b/API/Controllers/GroupCandidatesController.cs
@@ -23,13 +23,13 @@ namespace StudyLib.API.Controllers
             _context = context;
         }
 
-        [HttpGet("{groupId}")]
+        [HttpGet("list/{groupId}")]
         public async Task<ActionResult<IEnumerable<GroupCandidate>>> GetGroupCandidates(long groupId)
         {
             return await _context.GroupCandidates.Where(g => g.Group.ID == groupId).ToListAsync();
         }
 
-        [HttpPost]
+        [HttpPost("join-request")]
         public async Task<ActionResult<GroupCandidate>> GroupCandidate(GroupCandidate groupCandidate)
         {
             _context.GroupCandidates.Add(groupCandidate);
@@ -38,7 +38,7 @@ namespace StudyLib.API.Controllers
             return CreatedAtAction("GetGroupCandidate", groupCandidate);
         }
 
-        [HttpDelete("{groupId}/{userId}")]
+        [HttpDelete("delete/{groupId}/{userId}")]
         public async Task<IActionResult> DeleteGroupCandidate(long groupId, string userId)
         {
             var groupCandidate = await _context.GroupCandidates.Where(g => g.Group.ID == groupId && g.User.Id == userId).FirstAsync();
diff --git a/API/Controllers/GroupsController.cs b/API/Controllers/GroupsController.cs
index 8a5ec98..8559fd4 100644
--- a/API/Controllers/GroupsController.cs
+++ b/API/Controllers/GroupsController.cs
@@ -20,13 +20,26 @@ namespace StudyLib.API.Controllers
             _context = context;
         }
 
-        [HttpGet]
+        [HttpGet("list")]
         public async Task<ActionResult<IEnumerable<Group>>> GetGroups()
         {
             return await _context.Groups.Include(g => g.Users).Include(g => g.Subjects).ToListAsync();
         }
 
-        [HttpGet("{id}")]
+        [HttpGet("current-user-groups/{userId}")]
+        public async Task<ActionResult<IEnumerable<Group>>> GetCurrentUserGroups(string userId)
+        {
+            var user = await _context.Users.FindAsync(userId);
+            
+            if (user == null)
+            {
+                return NoContent();
+            }
+
+           return Ok(user.Groups);
+        }
+
+        [HttpGet("get-by-id/{id}")]
         public async Task<ActionResult<Group>> GetGroup(long id)
         {
             var group = await _context.Groups.Where(g => g.ID == id).Include(g => g.Users).Include(g => g.Subjects).SingleOrDefaultAsync();
@@ -39,7 +52,7 @@ namespace StudyLib.API.Controllers
             return group;
         }
 
-        [HttpPut("{id}")]
+        [HttpPut("update/{id}")]
         public async Task<IActionResult> PutGroup(long id, Group group)
         {
             if (id != group.ID)
@@ -68,7 +81,37 @@ namespace StudyLib.API.Controllers
             return NoContent();
         }
 
-        [HttpPost]
+        [HttpGet("leave/{id}/{userId}")]
+        public async Task<IActionResult> LeaveGroup(long id, string userId)
+        {
+            var user = await _context.Users.FindAsync(userId);
+
+            var groups = user.Groups.Where(g => g.ID != id).ToList();
+
+            user.Groups = groups;
+
+            _context.Entry(user).State = EntityState.Modified;
+
+            try
+            {
+                await _context.SaveChangesAsync();
+            }
+            catch (DbUpdateConcurrencyException)
+            {
+                if (!GroupExists(id))
+                {
+                    return NotFound();
+                }
+                else
+                {
+                    throw;
+                }
+            }
+
+            return NoContent();
+        }
+
+        [HttpPost("add")]
         public async Task<ActionResult<Group>> PostGroup(Group group)
         {
             _context.Groups.Add(group);
@@ -78,7 +121,7 @@ namespace StudyLib.API.Controllers
             return CreatedAtAction("GetGroup", new { id = group.ID }, group);
         }
 
-        [HttpDelete("{id}")]
+        [HttpDelete("delete/{id}")]
         public async Task<ActionResult<Group>> DeleteGroup(long id)
         {
             var group = await _context.Groups.FindAsync(id);
diff --git a/API/Controllers/SubjectDeleteRequestsController.cs b/API/Controllers/SubjectDeleteRequestsController.cs
index 0bdaae5..4c2f376 100644
--- a/API/Controllers/SubjectDeleteRequestsController.cs
+++ b/API/Controllers/SubjectDeleteRequestsController.cs
@@ -21,13 +21,13 @@ namespace StudyLib.API.Controllers
             _context = context;
         }
 
-        [HttpGet("list")]
-        public async Task<ActionResult<IEnumerable<SubjectDeleteRequest>>> GetSubjectDeleteRequest()
+        [HttpGet("list-by-group-id/{groupId}")]
+        public async Task<ActionResult<IEnumerable<SubjectDeleteRequest>>> GetSubjectDeleteRequest(long groupId)
         {
-            return await _context.SubjectDeleteRequests.Include(s => s.Subject).ToListAsync();
+            return await _context.SubjectDeleteRequests.Where(s => s.Subject.GroupId == groupId).Include(s => s.Subject).ToListAsync();
         }
 
-        [HttpPost("approveDeletion")]
+        [HttpPost("approve")]
         public async Task<ActionResult<SubjectDeleteRequest>> ApproveSubjectDeleteRequest(SubjectDeleteRequest deletionRequest)
         {
             var subjectDeleteRequest = await _context.SubjectDeleteRequests.Where(s => s.ID == deletionRequest.ID).Include(s => s.Subject).SingleOrDefaultAsync();
@@ -43,7 +43,7 @@ namespace StudyLib.API.Controllers
             return NoContent();
         }
 
-        [HttpPost("addDeletionRequest")]
+        [HttpPost("add")]
         public async Task<ActionResult<SubjectDeleteRequest>> AddSubjectDeleteRequest(SubjectDeleteRequest deletionRequest)
         {
             _context.SubjectDeleteRequests.Add(deletionRequest);
@@ -52,7 +52,7 @@ namespace StudyLib.API.Controllers
             return NoContent();
         }
 
-        [HttpDelete("cancelDeletion/{id}")]
+        [HttpDelete("cancel/{id}")]
         public async Task<IActionResult> CancelSubjectDeleteRequest(long id)
         {
             var subjectDeleteRequest = await _context.SubjectDeleteRequests.FindAsync(id);
diff --git a/API/Controllers/SubjectsController.cs b/API/Controllers/SubjectsController.cs
index f8030bd..bc251f7 100644
--- a/API/Controllers/SubjectsController.cs
+++ b/API/Controllers/SubjectsController.cs
@@ -24,15 +24,13 @@ namespace StudyLib.API.Controllers
             _context = context;
         }
 
-        // GET: api/Subjects
-        [HttpGet]
-        public async Task<ActionResult<IEnumerable<Subject>>> GetSubjects()
+        [HttpGet("list-by-group-id/{groupId}")]
+        public async Task<ActionResult<IEnumerable<Subject>>> GetSubjects(long groupId)
         {
-            return await _context.Subjects.Include(s => s.Comments).Include(s => s.Assignments).Include(s => s.Tests).ToListAsync();
+            return await _context.Subjects.Where(s => s.Group.ID == groupId).Include(s => s.Comments).Include(s => s.Assignments).Include(s => s.Tests).ToListAsync();
         }
 
-        // GET: api/Subjects/5
-        [HttpGet("{id}")]
+        [HttpGet("get-by-id/{id}")]
         public async Task<ActionResult<Subject>> GetSubject(long id)
         {
             var subject = await _context.Subjects.Where(s => s.ID == id).Include(s => s.Comments).Include(s => s.Assignments).Include(s => s.Tests).SingleOrDefaultAsync();
@@ -45,10 +43,7 @@ namespace StudyLib.API.Controllers
             return subject;
         }
 
-        // PUT: api/Subjects/5
-        // To protect from overposting attacks, enable the specific properties you want to bind to, for
-        // more details, see https://go.microsoft.com/fwlink/?linkid=2123754.
-        [HttpPut("{id}")]
+        [HttpPut("update/{id}")]
         public async Task<IActionResult> PutSubject(long id, Subject subject)
         {
             if (id != subject.ID)
@@ -112,10 +107,7 @@ namespace StudyLib.API.Controllers
             return NoContent();
         }
 
-        // POST: api/Subjects
-        // To protect from overposting attacks, enable the specific properties you want to bind to, for
-        // more details, see https://go.microsoft.com/fwlink/?linkid=2123754.
-        [HttpPost]
+        [HttpPost("add")]
         public async Task<ActionResult<Subject>> PostSubject(Subject subject)
         {
             _context.Subjects.Add(subject);
@@ -126,7 +118,7 @@ namespace StudyLib.API.Controllers
         }
 
         // DELETE: api/Subjects/5
-        [HttpDelete("{id}")]
+        [HttpDelete("delete/{id}")]
         public async Task<ActionResult<Subject>> DeleteSubject(long id)
         {
             var subject = await _context.Subjects.FindAsync(id);
diff --git a/API/Data/StudyLibDataSeeder.cs b/API/Data/StudyLibDataSeeder.cs
index f560236..8bd931c 100644
--- a/API/Data/StudyLibDataSeeder.cs
+++ b/API/Data/StudyLibDataSeeder.cs
@@ -11,7 +11,7 @@ namespace StudyLib.API.Data
         public static void Initialize(StudyLibContext context)
         {
 
-            if (context.Subjects.Any())
+           /* if (context.Subjects.Any())
             {
                 return;
             }
@@ -60,7 +60,7 @@ namespace StudyLib.API.Data
                 }
             );
 
-            context.SaveChanges();
+            context.SaveChanges();*/
 
         }
 
diff --git a/API/Models/Subject.cs b/API/Models/Subject.cs
index 8cc96f3..6723a24 100644
--- a/API/Models/Subject.cs
+++ b/API/Models/Subject.cs
@@ -18,6 +18,10 @@ namespace StudyLib.Models
 
         public bool MainExam { get; set; }
 
+        public long GroupId { get; set; }
+
+        public Group Group { get; set; }
+
         public DateTime ExamDate { get; set; }
 
         public ICollection<Test> Tests { get; set; }
diff --git a/Migrations/20201223201708_AddedGroupToSubject.Designer.cs b/Migrations/20201223201708_AddedGroupToSubject.Designer.cs
new file mode 100644
index 0000000..0a0227d
--- /dev/null
+++ b/Migrations/20201223201708_AddedGroupToSubject.Designer.cs
@@ -0,0 +1,570 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using StudyLib.API.Data;
+
+namespace StudyLib.Migrations
+{
+    [DbContext(typeof(StudyLibContext))]
+    [Migration("20201223201708_AddedGroupToSubject")]
+    partial class AddedGroupToSubject
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .UseIdentityColumns()
+                .HasAnnotation("Relational:MaxIdentifierLength", 128)
+                .HasAnnotation("ProductVersion", "5.0.0");
+
+            modelBuilder.Entity("GroupUser", b =>
+                {
+                    b.Property<long>("GroupsID")
+                        .HasColumnType("bigint");
+
+                    b.Property<string>("UsersId")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("GroupsID", "UsersId");
+
+                    b.HasIndex("UsersId");
+
+                    b.ToTable("GroupUser");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRole", b =>
+                {
+                    b.Property<string>("Id")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.Property<string>("ConcurrencyStamp")
+                        .IsConcurrencyToken()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Name")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<string>("NormalizedName")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NormalizedName")
+                        .IsUnique()
+                        .HasDatabaseName("RoleNameIndex")
+                        .HasFilter("[NormalizedName] IS NOT NULL");
+
+                    b.ToTable("AspNetRoles");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRoleClaim<string>", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int")
+                        .UseIdentityColumn();
+
+                    b.Property<string>("ClaimType")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("ClaimValue")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("RoleId")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("RoleId");
+
+                    b.ToTable("AspNetRoleClaims");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserClaim<string>", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int")
+                        .UseIdentityColumn();
+
+                    b.Property<string>("ClaimType")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("ClaimValue")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("UserId")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("UserId");
+
+                    b.ToTable("AspNetUserClaims");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserLogin<string>", b =>
+                {
+                    b.Property<string>("LoginProvider")
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("ProviderKey")
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("ProviderDisplayName")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("UserId")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("LoginProvider", "ProviderKey");
+
+                    b.HasIndex("UserId");
+
+                    b.ToTable("AspNetUserLogins");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserRole<string>", b =>
+                {
+                    b.Property<string>("UserId")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.Property<string>("RoleId")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("UserId", "RoleId");
+
+                    b.HasIndex("RoleId");
+
+                    b.ToTable("AspNetUserRoles");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserToken<string>", b =>
+                {
+                    b.Property<string>("UserId")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.Property<string>("LoginProvider")
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("Name")
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("Value")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("UserId", "LoginProvider", "Name");
+
+                    b.ToTable("AspNetUserTokens");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.Comment", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<long>("SubjectId")
+                        .HasColumnType("bigint");
+
+                    b.Property<string>("Text")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("SubjectId");
+
+                    b.ToTable("Comments");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.Group", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<string>("AdminId")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Name")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<int>("Year")
+                        .HasColumnType("int");
+
+                    b.HasKey("ID");
+
+                    b.ToTable("Groups");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.GroupCandidate", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<long>("GroupId")
+                        .HasColumnType("bigint");
+
+                    b.Property<string>("UserId")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("GroupId");
+
+                    b.HasIndex("UserId");
+
+                    b.ToTable("GroupCandidates");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.SubjectDeleteRequest", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<long>("SubjectId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("SubjectId");
+
+                    b.ToTable("SubjectDeleteRequests");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.User", b =>
+                {
+                    b.Property<string>("Id")
+                        .HasColumnType("nvarchar(450)");
+
+                    b.Property<int>("AccessFailedCount")
+                        .HasColumnType("int");
+
+                    b.Property<string>("ConcurrencyStamp")
+                        .IsConcurrencyToken()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Email")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<bool>("EmailConfirmed")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("FullName")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<bool>("LockoutEnabled")
+                        .HasColumnType("bit");
+
+                    b.Property<DateTimeOffset?>("LockoutEnd")
+                        .HasColumnType("datetimeoffset");
+
+                    b.Property<string>("NormalizedEmail")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<string>("NormalizedUserName")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<string>("PasswordHash")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("PhoneNumber")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<bool>("PhoneNumberConfirmed")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("SecurityStamp")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<bool>("TwoFactorEnabled")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("UserName")
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NormalizedEmail")
+                        .HasDatabaseName("EmailIndex");
+
+                    b.HasIndex("NormalizedUserName")
+                        .IsUnique()
+                        .HasDatabaseName("UserNameIndex")
+                        .HasFilter("[NormalizedUserName] IS NOT NULL");
+
+                    b.ToTable("AspNetUsers");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Assignment", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<DateTime>("Deadline")
+                        .HasColumnType("datetime2");
+
+                    b.Property<string>("Description")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<double>("FinalMarkPercent")
+                        .HasColumnType("float");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<long>("SubjectId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("SubjectId");
+
+                    b.ToTable("Assignments");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Subject", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<DateTime>("ExamDate")
+                        .HasColumnType("datetime2");
+
+                    b.Property<long>("GroupId")
+                        .HasColumnType("bigint");
+
+                    b.Property<string>("LabTeacher")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("LectureTeacher")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<bool>("MainExam")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("GroupId");
+
+                    b.ToTable("Subjects");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Test", b =>
+                {
+                    b.Property<long>("ID")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint")
+                        .UseIdentityColumn();
+
+                    b.Property<DateTime>("Date")
+                        .HasColumnType("datetime2");
+
+                    b.Property<double>("FinalMarkPercent")
+                        .HasColumnType("float");
+
+                    b.Property<string>("Scope")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<long>("SubjectId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("ID");
+
+                    b.HasIndex("SubjectId");
+
+                    b.ToTable("Tests");
+                });
+
+            modelBuilder.Entity("GroupUser", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.Group", null)
+                        .WithMany()
+                        .HasForeignKey("GroupsID")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.HasOne("StudyLib.API.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UsersId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRoleClaim<string>", b =>
+                {
+                    b.HasOne("Microsoft.AspNetCore.Identity.IdentityRole", null)
+                        .WithMany()
+                        .HasForeignKey("RoleId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserClaim<string>", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserLogin<string>", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserRole<string>", b =>
+                {
+                    b.HasOne("Microsoft.AspNetCore.Identity.IdentityRole", null)
+                        .WithMany()
+                        .HasForeignKey("RoleId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.HasOne("StudyLib.API.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserToken<string>", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.Comment", b =>
+                {
+                    b.HasOne("StudyLib.Models.Subject", "Subject")
+                        .WithMany("Comments")
+                        .HasForeignKey("SubjectId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Subject");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.GroupCandidate", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.Group", "Group")
+                        .WithMany("GroupCandidates")
+                        .HasForeignKey("GroupId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.HasOne("StudyLib.API.Models.User", "User")
+                        .WithMany()
+                        .HasForeignKey("UserId");
+
+                    b.Navigation("Group");
+
+                    b.Navigation("User");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.SubjectDeleteRequest", b =>
+                {
+                    b.HasOne("StudyLib.Models.Subject", "Subject")
+                        .WithMany()
+                        .HasForeignKey("SubjectId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Subject");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Assignment", b =>
+                {
+                    b.HasOne("StudyLib.Models.Subject", "Subject")
+                        .WithMany("Assignments")
+                        .HasForeignKey("SubjectId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Subject");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Subject", b =>
+                {
+                    b.HasOne("StudyLib.API.Models.Group", "Group")
+                        .WithMany("Subjects")
+                        .HasForeignKey("GroupId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Group");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Test", b =>
+                {
+                    b.HasOne("StudyLib.Models.Subject", "Subject")
+                        .WithMany("Tests")
+                        .HasForeignKey("SubjectId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Subject");
+                });
+
+            modelBuilder.Entity("StudyLib.API.Models.Group", b =>
+                {
+                    b.Navigation("GroupCandidates");
+
+                    b.Navigation("Subjects");
+                });
+
+            modelBuilder.Entity("StudyLib.Models.Subject", b =>
+                {
+                    b.Navigation("Assignments");
+
+                    b.Navigation("Comments");
+
+                    b.Navigation("Tests");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/Migrations/20201223201708_AddedGroupToSubject.cs b/Migrations/20201223201708_AddedGroupToSubject.cs
new file mode 100644
index 0000000..f69c667
--- /dev/null
+++ b/Migrations/20201223201708_AddedGroupToSubject.cs
@@ -0,0 +1,75 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace StudyLib.Migrations
+{
+    public partial class AddedGroupToSubject : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_Subjects_Groups_GroupID",
+                table: "Subjects");
+
+            migrationBuilder.RenameColumn(
+                name: "GroupID",
+                table: "Subjects",
+                newName: "GroupId");
+
+            migrationBuilder.RenameIndex(
+                name: "IX_Subjects_GroupID",
+                table: "Subjects",
+                newName: "IX_Subjects_GroupId");
+
+            migrationBuilder.AlterColumn<long>(
+                name: "GroupId",
+                table: "Subjects",
+                type: "bigint",
+                nullable: false,
+                defaultValue: 0L,
+                oldClrType: typeof(long),
+                oldType: "bigint",
+                oldNullable: true);
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_Subjects_Groups_GroupId",
+                table: "Subjects",
+                column: "GroupId",
+                principalTable: "Groups",
+                principalColumn: "ID",
+                onDelete: ReferentialAction.Cascade);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_Subjects_Groups_GroupId",
+                table: "Subjects");
+
+            migrationBuilder.RenameColumn(
+                name: "GroupId",
+                table: "Subjects",
+                newName: "GroupID");
+
+            migrationBuilder.RenameIndex(
+                name: "IX_Subjects_GroupId",
+                table: "Subjects",
+                newName: "IX_Subjects_GroupID");
+
+            migrationBuilder.AlterColumn<long>(
+                name: "GroupID",
+                table: "Subjects",
+                type: "bigint",
+                nullable: true,
+                oldClrType: typeof(long),
+                oldType: "bigint");
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_Subjects_Groups_GroupID",
+                table: "Subjects",
+                column: "GroupID",
+                principalTable: "Groups",
+                principalColumn: "ID",
+                onDelete: ReferentialAction.Restrict);
+        }
+    }
+}
diff --git a/Migrations/StudyLibContextModelSnapshot.cs b/Migrations/StudyLibContextModelSnapshot.cs
index cf98f3a..f7e8a55 100644
--- a/Migrations/StudyLibContextModelSnapshot.cs
+++ b/Migrations/StudyLibContextModelSnapshot.cs
@@ -359,7 +359,7 @@ namespace StudyLib.Migrations
                     b.Property<DateTime>("ExamDate")
                         .HasColumnType("datetime2");
 
-                    b.Property<long?>("GroupID")
+                    b.Property<long>("GroupId")
                         .HasColumnType("bigint");
 
                     b.Property<string>("LabTeacher")
@@ -377,7 +377,7 @@ namespace StudyLib.Migrations
 
                     b.HasKey("ID");
 
-                    b.HasIndex("GroupID");
+                    b.HasIndex("GroupId");
 
                     b.ToTable("Subjects");
                 });
@@ -527,9 +527,13 @@ namespace StudyLib.Migrations
 
             modelBuilder.Entity("StudyLib.Models.Subject", b =>
                 {
-                    b.HasOne("StudyLib.API.Models.Group", null)
+                    b.HasOne("StudyLib.API.Models.Group", "Group")
                         .WithMany("Subjects")
-                        .HasForeignKey("GroupID");
+                        .HasForeignKey("GroupId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Group");
                 });
 
             modelBuilder.Entity("StudyLib.Models.Test", b =>
diff --git a/Program.cs b/Program.cs
index 63371c8..5da24d9 100644
--- a/Program.cs
+++ b/Program.cs
@@ -14,7 +14,7 @@ namespace StudyLib
             {
                 var services = scope.ServiceProvider;
                 var context = services.GetService<StudyLibContext>();
-                StudyLibDataSeeder.Initialize(context);
+                //StudyLibDataSeeder.Initialize(context);
             }
             host.Run();
             // CreateHostBuilder(args).Build().Run();
diff --git a/bin/Debug/net5.0/StudyLib.dll b/bin/Debug/net5.0/StudyLib.dll
index f35b604..ddc55b2 100644
Binary files a/bin/Debug/net5.0/StudyLib.dll and b/bin/Debug/net5.0/StudyLib.dll differ
diff --git a/bin/Debug/net5.0/StudyLib.pdb b/bin/Debug/net5.0/StudyLib.pdb
index a32add5..c6ee5c3 100644
Binary files a/bin/Debug/net5.0/StudyLib.pdb and b/bin/Debug/net5.0/StudyLib.pdb differ
diff --git a/bin/Debug/net5.0/ref/StudyLib.dll b/bin/Debug/net5.0/ref/StudyLib.dll
index d987f15..6f29a0e 100644
Binary files a/bin/Debug/net5.0/ref/StudyLib.dll and b/bin/Debug/net5.0/ref/StudyLib.dll differ
diff --git a/obj/Debug/net5.0/StudyLib.csproj.CoreCompileInputs.cache b/obj/Debug/net5.0/StudyLib.csproj.CoreCompileInputs.cache
index da5ba41..f6e547c 100644
--- a/obj/Debug/net5.0/StudyLib.csproj.CoreCompileInputs.cache
+++ b/obj/Debug/net5.0/StudyLib.csproj.CoreCompileInputs.cache
@@ -1 +1 @@
-73a2189dbe3e51a4bc9dfe1696e53c26fb2ec4ea
+60b4309f39d35789ac308a57134eb3df9d09f22e
diff --git a/obj/Debug/net5.0/StudyLib.csprojAssemblyReference.cache b/obj/Debug/net5.0/StudyLib.csprojAssemblyReference.cache
index a714065..5abd609 100644
Binary files a/obj/Debug/net5.0/StudyLib.csprojAssemblyReference.cache and b/obj/Debug/net5.0/StudyLib.csprojAssemblyReference.cache differ
diff --git a/obj/Debug/net5.0/StudyLib.dll b/obj/Debug/net5.0/StudyLib.dll
index f35b604..ddc55b2 100644
Binary files a/obj/Debug/net5.0/StudyLib.dll and b/obj/Debug/net5.0/StudyLib.dll differ
diff --git a/obj/Debug/net5.0/StudyLib.pdb b/obj/Debug/net5.0/StudyLib.pdb
index a32add5..c6ee5c3 100644
Binary files a/obj/Debug/net5.0/StudyLib.pdb and b/obj/Debug/net5.0/StudyLib.pdb differ
diff --git a/obj/Debug/net5.0/ref/StudyLib.dll b/obj/Debug/net5.0/ref/StudyLib.dll
index d987f15..6f29a0e 100644
Binary files a/obj/Debug/net5.0/ref/StudyLib.dll and b/obj/Debug/net5.0/ref/StudyLib.dll differ