Is it possible to create 2 M:M relationships using the same join table?
I have the following situation and am receiving the exception:
Unhandled Exception: System.InvalidOperationException: Cannot create a relationship between 'ApplicationUser.ExpertTags' and 'UserTag.User', because there already is a relationship between 'ApplicationUser.StudyTags' and 'UserTag.User'. Navigation properties can only participate in a single relationship
In Tag:
public class Tag {
public Tag() {
Users = new List<UserTag>();
}
public int TagId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public ICollection<UserTag> Users { get; set; }
In ApplicationUser:
public class ApplicationUser : IdentityUser
{
public ApplicationUser()
{
StudyTags = new HashSet<UserTag>();
ExpertTags = new HashSet<UserTag>();
}
public string FirstName { get; set; }
public string LastName { get; set; }
public string Location { get; set; }
public ICollection<UserTag> StudyTags { get; set; }
public ICollection<UserTag> ExpertTags { get; set; }
}
In UserTag (CLR join):
public class UserTag
{
public string UserId { get; set; }
public ApplicationUser User { get; set; }
public int TagId { get; set; }
public Tag Tag { get; set; }
}
In ApplicationDbContext:
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<UserTag>()
.HasKey(x => new { x.UserId, x.TagId });
modelBuilder.Entity<UserTag>()
.HasOne(ut => ut.User)
.WithMany(u => u.StudyTags)
.HasForeignKey(ut => ut.UserId);
modelBuilder.Entity<UserTag>()
.HasOne(ut => ut.User)
.WithMany(u => u.ExpertTags)
.HasForeignKey(ut => ut.UserId);
modelBuilder.Entity<UserTag>()
.HasOne(ut => ut.Tag)
.WithMany(t => t.Users)
.HasForeignKey(ut => ut.TagId);
}
Do I need to create separate CLR classes? Something like UserStudyTag and UserExpertTag?
Thanks!
Step down to SQL DB. You want to have table UserTag with one UserId field. How EF should guess, which records in this table are related to StudyTags and which to ExpertTags collections?
You should duplicate something.
Either split UserTag to two tables (UserStudyTag and UserExpertTag), or make two UserId fields in UserTag, say ExpertUserId and StudyUserId. Both nullable, with only one having some value in each record.
Related
I get on creating Migration some Warnings like this one:
The foreign key property 'AppUserClaim.UserId1' was created in shadow state because a conflicting property with the simple name 'UserId' exists in the entity type, but is either not mapped, is already used for another relationship, or is incompatible with the associated primary key type. See https://aka.ms/efcore-relationships for information on mapping relationships in EF Core.
It applies to all entities with AppUser navigation property. Other navigation properties has no warning.
public class AppUser : IdentityUser<Guid>, IChangeTrackerObject
{
public string FirstName { get; set; }
public string LastName { get; set; }
[Column(TypeName = "text")]
public string ProfilePictureDataUrl { get; set; }
public string CreatedBy { get; set; }
public DateTime CreatedOn { get; set; }
public string ChangedBy { get; set; }
public DateTime? ChangedOn { get; set; }
public bool IsDeleted { get; set; }
public DateTime? DeletedOn { get; set; }
public bool IsActive { get; set; }
public string RefreshToken { get; set; }
public DateTime RefreshTokenExpiryTime { get; set; }
public virtual ICollection<AppUserClaim> Claims { get; set; }
public virtual ICollection<AppUserLogin> Logins { get; set; }
public virtual ICollection<AppUserToken> Tokens { get; set; }
public virtual ICollection<AppUserRole> UserRoles { get; set; }
public AppUser()
{
}
}
public class AppUserClaim : IdentityUserClaim<Guid>, IChangeTrackerObject
{
public string ChangedBy { get; set; }
public DateTime? ChangedOn { get; set; }
public string CreatedBy { get; set; }
public DateTime CreatedOn { get; set; }
public virtual AppUser User { get; set; }
}
private static void BuildIdentity(ModelBuilder modelBuilder)
{
modelBuilder.Entity<AppUser>(entity =>
{
entity.ToTable(name: "Users", schema);
entity.Property(e => e.Id).ValueGeneratedOnAdd();
// Each User can have many UserClaims
entity.HasMany(e => e.Claims)
.WithOne()
.HasForeignKey(uc => uc.UserId)
.IsRequired();
// Each User can have many UserLogins
entity.HasMany(e => e.Logins)
.WithOne()
.HasForeignKey(ul => ul.UserId)
.IsRequired();
// Each User can have many UserTokens
entity.HasMany(e => e.Tokens)
.WithOne()
.HasForeignKey(ut => ut.UserId)
.IsRequired();
// Each User can have many entries in the UserRole join table
entity.HasMany(e => e.UserRoles)
.WithOne()
.HasForeignKey(ur => ur.UserId)
.IsRequired();
});
modelBuilder.Entity<AppUserClaim>(entity =>
{
entity.ToTable("UserClaims", schema);
});
}
I ran into a similar issue. In my OnModelCreating method, I had flipped the order in which I was applying migrations.
protected override void OnModelCreating(ModelBuilder builder)
{
base.OnModelCreating(builder);
builder.ApplyConfigurationsFromAssembly(Assembly.GetExecutingAssembly());
}
Basically, it seemed like if the call to the base method came after the call to apply the configurations from my code, then the configurations in the base method would override my configurations, which gave me a similar error to what you had. So what I'm assuming is happening is you're calling BuildIdentity() after you call base.OnModelCreating(). You may need to reverse that order, otherwise the relationships defined in the default identity DB may take precedence.
I am quite new to EF Core 6.0. We currently have a projet to upgrade, we cannot change the actual tables (use by another program) so we use Database fisrt approch.
So I need to add some Permission on user (the database are in french) We curently have an UsagerEW table (user table) and we add an Permission Table and an joint table PermissionUsagerEW for the Many2Many. After doing Scaffold-dbContect here is the result:
UsagerEW (primary key is Code_Int)
public partial class UsagerEW
{
public UsagerEW()
{
PermissionUsagerEW = new HashSet<PermissionUsagerEW>();
RefreshToken = new HashSet<RefreshToken>();
}
public string Code { get; set; }
public string Nom { get; set; }
public string Email { get; set; }
public string ModeLogin { get; set; }
public string PasswordTemp { get; set; }
public DateTime? PasswordTempExp { get; set; }
public int code_int { get; set; }
public virtual ICollection<PermissionUsagerEW> PermissionUsagerEW { get; set; }
}
Pemrssion and PermissionUsagerEW
public partial class Permission
{
public Permission()
{
PermissionUsagerEW = new HashSet<PermissionUsagerEW>();
}
public int id { get; set; }
public string code { get; set; }
public string description { get; set; }
public int? moduleId { get; set; }
public virtual Module module { get; set; }
public virtual ICollection<PermissionUsagerEW> PermissionUsagerEW { get; set; }
}
public partial class PermissionUsagerEW
{
public int id { get; set; }
public int permissionId { get; set; }
public int usagerCodeInt { get; set; }
public virtual Permission permission { get; set; }
public virtual UsagerEW usagerCodeIntNavigation { get; set; }
}
That compile and I can "navigate with include" from UsagerEW and get an list of PermissionUsagerEW for a specific UsagerEW.
Now like I am in EF COre 6.0 that supposed to support Many2Many
I add this nav propertie in the Permnission class
public virtual ICollection<UsagerEW> UsagerEW { get; set; }
and this in the UsagerEW class:
public virtual ICollection<Permission> Permission { get; set; }
But I got execution error either I just try to load some user wintout any include:
UsagerEW user = _EWContext.UsagerEW.Where(u=>u.Code == usagerId).SingleOrDefault();
System.InvalidOperationException: 'Cannot use table
'PermissionUsagerEW' for entity type 'PermissionUsagerEW
(Dictionary<string, object>)' since it is being used for entity type
'PermissionUsagerEW' and potentially other entity types, but there is
no linking relationship. Add a foreign key to 'PermissionUsagerEW
(Dictionary<string, object>)' on the primary key properties and
pointing to the primary key on another entity type mapped to
'PermissionUsagerEW'.'
The FK are detect by the scaffold:
modelBuilder.Entity<PermissionUsagerEW>(entity =>
{
entity.HasOne(d => d.permission)
.WithMany(p => p.PermissionUsagerEW)
.HasForeignKey(d => d.permissionId)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_PermissionUsager_Permission");
entity.HasOne(d => d.usagerCodeIntNavigation)
.WithMany(p => p.PermissionUsagerEW)
.HasForeignKey(d => d.usagerCodeInt)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_PermissionUsager_Usager");
});
Any idea?
---EDIT 1
I change your code to reflect the scaffolded PermissionUsagerEW table:
//--UsagewrEW
modelBuilder.Entity<UsagerEW>()
.HasKey(u => u.code_int);
modelBuilder.Entity<UsagerEW>()
.HasMany(u => u.Permissions)
.WithMany(p => p.Users)
.UsingEntity<PermissionUsagerEW>(
p => p.HasOne(e => e.permission)
.WithMany()
.HasForeignKey(e => e.permissionId),
p => p.HasOne(p => p.usagerCodeIntNavigation)
.WithMany()
.HasForeignKey(e => e.usagerCodeInt)
);
modelBuilder.Entity<PermissionUsagerEW>()
.HasOne(p => p.usagerCodeIntNavigation)
.WithMany()
.HasForeignKey(p => p.usagerCodeInt);
When testing with
UsagerEW user = _EWContext.UsagerEW.Where(u=>u.Code == usagerId).Include(u => u.Permissions).SingleOrDefault();
Now I got this error:
Microsoft.Data.SqlClient.SqlException: 'Invalid column name
'UsagerEWcode_int'.'
I think EF tries to link something automatically. I do not have any UsagerEWcode_int in my solution.
EDIT2:
There is the SQL generated. Wierd column name and some repetition...
SELECT [u].[code_int], [u].[Administrateur], [u].[Code], [u].[Email], [u].[EmpContact], [u].[Inactif], [u].[KelvinConfig], [u].[LectureSeule], [u].[ModeLogin], [u].[Nom], [u].[ParamRole], [u].[Password], [u].[PasswordTemp], [u].[PasswordTempExp], [u].[RestreintCommContrat], [u].[RestreintProjet], [u].[Role], [u].[UsagerAD], [u].[doitChangerPW], [u].[estSuperviseur], [u].[idSuperviseur], [u].[infoSession], [u].[paramRole2], [u].[permsGrps], [t].[id], [t].[Permissionid], [t].[UsagerEWcode_int], [t].[permissionId0], [t].[usagerCodeInt], [t].[id0], [t].[code], [t].[description], [t].[moduleId]
FROM [UsagerEW] AS [u]
LEFT JOIN (
SELECT [p].[id], [p].[Permissionid], [p].[UsagerEWcode_int], [p].[permissionId] AS [permissionId0], [p].[usagerCodeInt], [p0].[id] AS [id0], [p0].[code], [p0].[description], [p0].[moduleId]
FROM [PermissionUsagerEW] AS [p]
INNER JOIN [Permission] AS [p0] ON [p].[permissionId] = [p0].[id]
) AS [t] ON [u].[code_int] = [t].[usagerCodeInt]
WHERE [u].[Code] = #__usagerId_0
ORDER BY [u].[code_int], [t].[id]
You can configure direct Many-to-Many relationships with an existing database, and you can have the linking entity in the model or exclude it. There are several examples in the docs. And you can leave the foreign key properties in the model, or you can replace them with shadow properties. But the Scaffolding code doesn't do any of this for you. It creates the simplest correct model for the database schema.
Also you usually should rename the entities and properties to align with .NET coding conventions.
Anyway something like this should work:
public partial class UsagerEW
{
public string Code { get; set; }
public string Nom { get; set; }
public string Email { get; set; }
public string ModeLogin { get; set; }
public string PasswordTemp { get; set; }
public DateTime? PasswordTempExp { get; set; }
public int code_int { get; set; }
public virtual ICollection<Permission> Permissions { get; } = new HashSet<Permission>();
}
public partial class Permission
{
public int Id { get; set; }
public string Code { get; set; }
public string Description { get; set; }
public int? ModuleId { get; set; }
//public virtual Module module { get; set; }
public virtual ICollection<UsagerEW> Users { get; } = new HashSet<UsagerEW>();
}
public partial class PermissionUsagerEW
{
public int Id { get; set; }
public int PermissionId { get; set; }
public int UsagerCodeInt { get; set; }
public virtual Permission Permission { get; set; }
public virtual UsagerEW User { get; set; }
}
public class Db : DbContext
{
protected override void OnModelCreating(ModelBuilder builder)
{
builder.Entity<UsagerEW>()
.HasKey(u => u.code_int);
builder.Entity<UsagerEW>()
.HasMany(u => u.Permissions)
.WithMany(p => p.Users)
.UsingEntity<PermissionUsagerEW>(
p => p.HasOne(e => e.Permission)
.WithMany()
.HasForeignKey(e => e.PermissionId),
p => p.HasOne(p => p.User)
.WithMany()
.HasForeignKey( e => e.UsagerCodeInt)
);
builder.Entity<PermissionUsagerEW>()
.HasOne(p => p.User)
.WithMany()
.HasForeignKey(p => p.UsagerCodeInt);
foreach (var prop in builder.Model.GetEntityTypes().SelectMany(e => e.GetProperties()))
{
prop.SetColumnName(char.ToLower(prop.Name[0]) + prop.Name.Substring(1));
}
base.OnModelCreating(builder);
}
But when you're working in a database-first workflow, there's a downside to deeply customizing the EF model: you loose the ability to regenerate the EF model from the database.
So you can use a "nice" customized EF model, or a "plain" scaffolded model. If you customize the model, you can no longer regenerate it, and need to alter it to match future database changes by hand.
You can apply some customizations, though, like the convention-based property-to-column and entity-to-table mappings in the example. But changing the generated "indirect many-to-many" to "direct many-to-many" will prevent you from regenerating the EF model through scaffolding.
I have followed the instructions for the workaround for many-to-many described in Issue #1368 and the Docs Here... but when I try to navigate, it always returns null.
My Models:
public class Organization
{
public Guid OrganizationID { get; set; }
//...
public ICollection<OrganizationSubscriptionPlan> OrganizationSubscriptionPlans { get; set; }
}
public class SubscriptionPlan
{
public int SubscriptionPlanID { get; set; }
//...
public ICollection<OrganizationSubscriptionPlan> OrganizationSubscriptionPlans { get; set; }
public class OrganizationSubscriptionPlan
{
[ForeignKey("Organization")]
public Guid OrganizationID { get; set; }
public Organization Organization { get; set; }
[ForeignKey("SubscriptionPlan")]
public int SubscriptionPlanID { get; set; }
public SubscriptionPlan SubscriptionPlan { get; set; }
}
ApplicationDbContext:
protected override void OnModelCreating(ModelBuilder builder)
{
base.OnModelCreating(builder);
builder.Entity<OrganizationSubscriptionPlan>().HasKey(x => new { x.OrganizationID, x.SubscriptionPlanID });
builder.Entity<OrganizationSubscriptionPlan>().HasOne(x => x.Organization).WithMany(x => x.OrganizationSubscriptionPlans).HasForeignKey(x => x.OrganizationID);
builder.Entity<OrganizationSubscriptionPlan>().HasOne(x => x.SubscriptionPlan).WithMany(x => x.OrganizationSubscriptionPlans).HasForeignKey(x => x.SubscriptionPlanID);
}
And my Query:
var organizations = _context.Organizations
.Include(o => o.OrganizationSubscriptionPlans);
foreach (var organization in organizations)
{
//....
var subscriptions = organization.OrganizationSubscriptionPlans
.Select(s => s.SubscriptionPlan);
// ^^^^^^^^^^^ why is subscriptions always null?
}
The "organizations" query returns the results as expected, including the list of OrganizationSubscriptionPlans within each one, but when I try to navigate to them in the foreach loop the "subscriptions" query returns null every time. What am I doing wrong?
Turns out it's a Lazy Loading issue. You have to "Include" the joining entity and then "ThenInclude" the other entity.
var organizations = _context.Organizations
.Include(o => o.OrganizationSubscriptionPlans)
.ThenInclude(s => s.SubscriptionPlan);
ForeignKey attr is to decorate reference properties to indicate them what primitive property hold the FK value.
public class OrganizationSubscriptionPlan
{
public Guid OrganizationID { get; set; }
[ForeignKey("OrganizationID")]
public Organization Organization { get; set; }
public int SubscriptionPlanID { get; set; }
[ForeignKey("SubscriptionPlanID")]
public SubscriptionPlan SubscriptionPlan { get; set; }
}
I am having a problem where my Entity Framework navigation properties are null. My two models are Order and OrderLine:
class Order
{
public string CustomerId { get; set; }
public string OrderNumber { get; set; }
public ICollection<OrderLine> Lines { get; set; }
}
class OrderLine
{
public int LineNumber { get; set; }
public string OrderNumber { get; set; }
public string ProductId { get; set; }
public int Quantity { get; set; }
public Order Order { get; set; }
}
My Context class looks like this
class MyContext : DbContext
{
public DbSet<Order> Orders { get; set; }
public DbSet<OrderLine> OrderLines { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Order>()
.HasKey(p => p.OrderNumber);
modelBuilder.Entity<OrderLine>()
.HasKey(p => new { p.OrderNumber, p.LineNumber });
modelBuilder.Entity<OrderLine>()
.HasRequired(p => p.Order)
.WithMany(p => p.Lines)
.HasForeignKey(p => p.OrderNumber);
}
}
When I run the following code, my orders load (the message box shows the correct count), but the Order.Lines collection is null.
List<Order> orders = (from o in context.Orders select o).ToList();
// This message box shows the correct number of orders
MessageBox.Show(orders.Count.ToString());
// This line crashes because orders[0].Lines is null. There are lines in the database that should be joining to orders[0]
MessageBox.Show(orders[0].Lines.Count.ToString());
I've looked at a lot of examples, and I can't figure out what I'm doing incorrectly.
You need to declare the navigation properties as virtual in order to be lazy loaded:
public class Order
{
//...
public virtual ICollection<OrderLine> Lines { get; set; }
}
public class OrderLine
{
//...
public virtual Order Order { get; set; }
}
For more info check this link to see all the requirements you need to follow.
I'm having issues applying multiple relationships (or possibly foreignkey) on two POCO objects. I've got the first relationship many-to-many working and when the database is created it creates the three tables (Projects, Users and ProjectsUsers) needed for the relationship.
Code so far:
public class Project
{
public int ProjectId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public DateTime? StartDate { get; set; }
public DateTime? CompletionDate { get; set; }
public bool Deleted { get; set; }
public ICollection<User> Users { get; set; }
}
public class User
{
public User()
{
Name = new Name();
}
public int UserId { get; set; }
public string LoginId { get; set; }
public string Password { get; set; }
public Name Name { get; set; }
public ICollection<Project> ManagedProjects { get; set; }
}
public class ProjectConfiguration : EntityTypeConfiguration<Project>
{
public ProjectConfiguration()
{
HasMany(x => x.Users)
.WithMany(x => x.ManagedProjects);
}
}
public UserConfiguration()
{
HasMany(x => x.ManagedProjects)
.WithMany(x => x.Users);
}
Now I want to add an optional one-to-one relationship of Project.ManagingUser -> User. However, I can't seem to figure out how to indicate this in the configuration.
Code for what I think is needed:
public class Project
{
public int ProjectId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public DateTime? StartDate { get; set; }
public DateTime? CompletionDate { get; set; }
public bool Deleted { get; set; }
public int? ManagingUserId { get; set; }
public User ManagingUser { get; set; }
public ICollection<User> Users { get; set; }
}
I don't think the User object needs to change.
This shows my last attempt on mapping the new relationship:
public ProjectConfiguration()
{
HasMany(p => p.Users)
.WithMany(u => u.Projects);
this.HasOptional(p => p.ManagingUser)
.WithOptionalDependent()
.Map(m=>m.MapKey("ManagingUserId"))
.WillCascadeOnDelete(false);
}
What is happening when the database is created, I now end up with only two tables (Projects and Users). And it looks like it is only trying to setup the one-to-one relationship.
Can someone tell me what I'm missing?
Richard I've not changed the UserConfiguration and below is the DbContext:
public class MyDbContext : DbContext
{
public MyDbContext() : base(Properties.Settings.Default.ConnectionString)
{
}
public DbSet<User> Users { get; set; }
public DbSet<Project> Projects { get; set; }
}
You probably want WithMany instead of WithOptionalDependent - it's a one:many relationship, not a one:one.
HasOptional(p => p.ManagingUser)
.WithMany()
.HasForeignKey(m => m.ManagingUserId)
.WillCascadeOnDelete(false);
EDIT
I think you're missing the OnModelCreating override from the DbContext class:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Configurations.Add(new ProjectConfiguration());
modelBuilder.Configurations.Add(new UserConfiguration());
}