EF6 Many-to-many can not delete - .net-core

Question

I have created table using EF6 core using below code.
The problem is, UserA , UserB created and assigned the different claims. No issue at all. When assigning existing claims (for example UserB is assigned UserA's claims --> [tying to do] delete UserB's claims & Changing UserB's subject to UserA's subject) then I am deleting UserB's claim by subjectId this create the primary key duplicate issue in UserUserClaims tables bcos SubjectId and ClaimId already existing
public class User
{
[Key]
public Guid UserId { get; set; }
[MaxLength(200)]
public string Username { get; set; }
[Required]
public Guid Subject { get; set; }
public ICollection<UserClaim> Claims { get; set; } = new List<UserClaim>();
public List<UserClaimRelation> UserClaimRelations { get; set; }
}
public class UserClaim
{
[Key]
public Guid UserClaimId { get; set; }
[MaxLength(250)]
[Required]
public string Type{ get; set; }
[Required]
public Guid Subject { get; set; }
[MaxLength(250)]
[Required]
public string Value { get; set; }
public ICollection<User> Users { get; set; }
public List<UserClaimRelation> UserClaimRelations { get; set; }
}
public class UserClaimRelation
{
public Guid UserClaimId{ get; set; }
public UserClaim Claim { get; set; }
public Guid UserSubject{ get; set; }
public User User { get; set; }
}
public class MyDbContext: DbContext
{
public DbSet<User> Users { get; set; }
public DbSet<UserClaim> UserClaims { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<User>()
.HasMany(p => p.Claims)
.WithMany(p => p.Users)
.UsingEntity<UserClaimRelation>(
j => j
.HasOne(pt => pt.Claim)
.WithMany(t => t.UserClaimRelations)
.HasPrincipalKey(f => f.UserClaimId),
j => j.HasOne(p => p.User)
.WithMany(t => t.UserClaimRelations)
.HasPrincipalKey( t => t.Subject),
j => j.HasKey( t => new {t.UserClaimId, t.UserSubject})
);
}
I am trying to delete the Claims by SubjectId
public async Task<bool> DeleteUserClaimsBySubjectAsync(Guid subject)
{
if (subject == Guid.Empty)
{
throw new ArgumentNullException(nameof(subject));
}
var claims = await _context.UserClaims
.Where(x => x.Subject == subject).ToListAsync();
foreach (var claim in claims)
{
_context.UserClaims.Remove(claim);
}
//_context.UserClaims.RemoveRange(claims);
return (await _context.SaveChangesAsync() > 0);
}
While deleting claims in DeleteUserClaimsBySubjectAsync I am getting the below error
SqlException: Violation of PRIMARY KEY constraint 'PK_UserClaimRelation'. Cannot insert duplicate key in object 'dbo.UserClaimRelation'. The duplicate key value is (13229d33-99e0-41b3-b18d-4f72127e3971, 8acbbd40-1608-41f2-de59-08d9b58b83d3).
SQL Profiler Query
exec sp_executesql N'SET NOCOUNT ON;
INSERT INTO [UserClaimRelation] ([UserClaimId], [UserSubject])
VALUES (#p0, #p1),
(#p2, #p3),
(#p4, #p5),
(#p6, #p7),
(#p8, #p9);
DELETE FROM [UserClaims]
WHERE [UserClaimId] = #p10 AND [ConcurrencyStamp] = #p11;
SELECT ##ROWCOUNT;
DELETE FROM [UserClaims]
WHERE [UserClaimId] = #p12 AND [ConcurrencyStamp] = #p13;
SELECT ##ROWCOUNT;
DELETE FROM [UserClaims]
WHERE [UserClaimId] = #p14 AND [ConcurrencyStamp] = #p15;
SELECT ##ROWCOUNT;
DELETE FROM [UserClaims]
WHERE [UserClaimId] = #p16 AND [ConcurrencyStamp] = #p17;
SELECT ##ROWCOUNT;
DELETE FROM [UserClaims]
WHERE [UserClaimId] = #p18 AND [ConcurrencyStamp] = #p19;
SELECT ##ROWCOUNT;
',N'#p0 uniqueidentifier,#p1 uniqueidentifier,#p2 uniqueidentifier,#p3 uniqueidentifier,#p4 uniqueidentifier,#p5 uniqueidentifier,#p6 uniqueidentifier,#p7 uniqueidentifier,#p8 uniqueidentifier,#p9 uniqueidentifier,#p10 uniqueidentifier,#p11 nvarchar(4000),#p12 uniqueidentifier,#p13 nvarchar(4000),#p14 uniqueidentifier,#p15 nvarchar(4000),#p16 uniqueidentifier,#p17 nvarchar(4000),#p18 uniqueidentifier,#p19 nvarchar(4000)',
#p0='6203BBC3-BD52-4E32-3DDD-08D9B86AB745',#p1='D860EFCA-22D9-47FD-8249-791BA61B07C7',
#p2='80B958C5-FF44-400F-3DDE-08D9B86AB745',#p3='D860EFCA-22D9-47FD-8249-791BA61B07C7',
#p4='A844CB59-5A00-488A-3DDF-08D9B86AB745',#p5='D860EFCA-22D9-47FD-8249-791BA61B07C7',#p6='794AB806-3215-45AF-3DE0-08D9B86AB745',#p7='D860EFCA-22D9-47FD-8249-791BA61B07C7',#p8='80EFF0DF-AE56-419A-3DE1-08D9B86AB745',#p9='D860EFCA-22D9-47FD-8249-791BA61B07C7',#p10='1A48CF6E-E1CD-4042-3DE4-08D9B86AB745',#p11=N'742674d8-3c59-4be4-ac09-38c6804acb66',#p12='258ABD95-6B2A-45CC-3DE6-08D9B86AB745',#p13=N'd206316a-71af-46b7-92e4-bddca669ad87',#p14='4FB1D2E3-18BE-4AFC-3DE3-08D9B86AB745',#p15=N'3eb17fb7-998b-47e1-a97f-3640cbd82b7a',#p16='6C2B9A18-5C8F-4068-3DE5-08D9B86AB745',#p17=N'415b2cc1-b50a-4ec8-872d-13b6342dcd33',#p18='951CEEA6-D057-4588-3DE2-08D9B86AB745',#p19=N'3dfd76dd-d515-4daa-893c-f1ae97aa063a'

Answer 1

Ok, so you want many-to-many relationship here - multiple user can have multiple different claims and multiple claims can be assigned to multiple users.
So first - Users:
public class User
{
[Key]
public Guid UserId { get; set; }
[MaxLength(200)]
public string Username { get; set; }
[Required]
public Guid Subject { get; set; }
public ICollection<UserClaim> Claims { get; set; } = new List<UserClaim>();
}
Then, UserClaims
public class UserClaim
{
[Key]
public Guid UserClaimId { get; set; }
[MaxLength(250)]
[Required]
public string Type{ get; set; }
[Required]
public Guid Subject { get; set; }
[MaxLength(250)]
[Required]
public string Value { get; set; }
public ICollection<User> Users { get; set; }
}
Notice that there is no navigation property leading to UserClaimRelation in any of the above. In the matter of fact, we remove this UserClaimRelation as an separate entity model entirely - it is not needed for this example. You can map it if you really want, but lets focus on making this work.
Now, the relationship setup:
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<User>()
.HasMany(x => x.Claims)
.WithMany(x => x.Users)
.UsingEntity<Dictionary<string, object>>(
"UserClaimRelation",
x => x.HasOne<User>().WithMany(),
x => x.HasOne<UserClaim>().WithMany(),
x => x.ToTable("UserClaimRelation"));
}
Now, after updating / recreating / reapplying migrations to the database (depends on your way of doing things) you should be able to delete the claims by subject without modifying your DeleteUserClaimsBySubjectAsync method.
This should set it all up and create intermediary table.
Validate this code, I was typing from memory

Answer 2

I applied the code. Tables created like below image. But when I try to update an userA's subject with userB's Subject (same claims of userB) I got the below error
Updating
SqlException: Violation of PRIMARY KEY constraint 'PK_UserClaimRelation'. Cannot insert duplicate key in object 'dbo.UserClaimRelation'. The duplicate key value is (bd7eb87f-2a5f-4921-758e-08d9b97d3121, 13229d33-99e0-41b3-b18d-4f72127e3971). bcos its trying to insert in UserClaimRelation, same as the profiler query I given initially.