I open this question because of this unanswered/duplicate question of mine:
Multiple identity columns specified for table exception
The answer to this question is here:
Cant remove identity attribute from PK
in short: "I have to Re-Create my sql table in the migration Up method"
I have a User has many SchoolclassCode relation:
public class User
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<SchoolclassCode> SchoolclassCodes { get; set; }
}
public class SchoolclassCode
{
public int Id { get; set; }
public string Schoolclass { get; set; }
public string Type { get; set; }
public User User { get; set; }
public int UserId { get; set; }
}
That is my INIT migration
public partial class Init: DbMigration
{
public override void Up()
{
CreateTable(
"dbo.SchoolclassCodes",
c => new
{
Id = c.Int(nullable: false, identity: true),
Schoolclass = c.String(),
Type = c.String(),
User_Id = c.Int(),
})
.PrimaryKey(t => t.Id)
.ForeignKey("dbo.Users", t => t.User_Id)
.Index(t => t.User_Id);
CreateTable(
"dbo.Users",
c => new
{
Id = c.Int(nullable: false, identity: true),
Name = c.String(),
})
.PrimaryKey(t => t.Id);
}
public override void Down()
{
DropForeignKey("dbo.SchoolclassCodes", "User_Id", "dbo.Users");
DropIndex("dbo.SchoolclassCodes", new[] { "User_Id" });
DropTable("dbo.Users");
DropTable("dbo.SchoolclassCodes");
}
}
That is my Second migration which is throwing the error: invalid column name 'User_Id' when I do 'Update-database'
public partial class ReCreateTable : DbMigration
{
public override void Up()
{
// backup schoolclassCodes table
DropTable("SchoolclassCodes");
CreateTable("SchoolclassCodes",
c => new
{
Id = c.Int(nullable: false, identity: true),
Schoolclass = c.String(maxLength: 3), // 12a,7b
Type = c.String(),
UserId = c.Int(nullable: false,identity:false)
})
.PrimaryKey(t => t.Id)
.ForeignKey("Users", t => t.UserId, cascadeDelete: true)
.Index(s => s.Schoolclass, unique: true);
// Delete Table Users
Sql("Delete from Users");
// Re-Insert data
SqlFile("./Migrations/data.sql");
}
public override void Down()
{
//
}
}
What do I wrong, that the update-database fails?
If you are going to delete everything you created in the first migration, drop them as described in the Down() code:
// backup schoolclassCodes table
DropForeignKey("dbo.SchoolclassCodes", "User_Id", "dbo.Users");
DropIndex("dbo.SchoolclassCodes", new[] { "User_Id" });
// DropTable("dbo.Users");
DropTable("dbo.SchoolclassCodes");
An observation, seems like you are coupling the need to keep your old data with migrations. I would separate the two.
First, save your old data. If the volume is low consider adding it to a Seed() method. Otherwise rename the tables in SQL and use SQL to repopulate them after migrations adds the corrected tables back.
Migrations are intended to let you build a database from your models, so I would delete both migrations and add a single new migration that represents your current model.
I've been wrestling with this for a while and can't quite figure out what's happening. I have a Card entity which contains Sides (usually 2) - and both Cards and Sides have a Stage. I'm using EF Codefirst migrations and the migrations are failing with this error:
Introducing FOREIGN KEY constraint 'FK_dbo.Sides_dbo.Cards_CardId' on
table 'Sides' may cause cycles or multiple cascade paths. Specify ON
DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY
constraints.
Here's my Card entity:
public class Card
{
public Card()
{
Sides = new Collection<Side>();
Stage = Stage.ONE;
}
[Key]
[Required]
public virtual int CardId { get; set; }
[Required]
public virtual Stage Stage { get; set; }
[Required]
[ForeignKey("CardId")]
public virtual ICollection<Side> Sides { get; set; }
}
Here's my Side entity:
public class Side
{
public Side()
{
Stage = Stage.ONE;
}
[Key]
[Required]
public virtual int SideId { get; set; }
[Required]
public virtual Stage Stage { get; set; }
[Required]
public int CardId { get; set; }
[ForeignKey("CardId")]
public virtual Card Card { get; set; }
}
And here's my Stage entity:
public class Stage
{
// Zero
public static readonly Stage ONE = new Stage(new TimeSpan(0, 0, 0), "ONE");
// Ten seconds
public static readonly Stage TWO = new Stage(new TimeSpan(0, 0, 10), "TWO");
public static IEnumerable<Stage> Values
{
get
{
yield return ONE;
yield return TWO;
}
}
public int StageId { get; set; }
private readonly TimeSpan span;
public string Title { get; set; }
Stage(TimeSpan span, string title)
{
this.span = span;
this.Title = title;
}
public TimeSpan Span { get { return span; } }
}
What's odd is that if I add the following to my Stage class:
public int? SideId { get; set; }
[ForeignKey("SideId")]
public virtual Side Side { get; set; }
The migration runs successfully. If I open up SSMS and look at the tables, I can see that Stage_StageId has been added to Cards (as expected/desired), however Sides contains no reference to Stage (not expected).
If I then add
[Required]
[ForeignKey("StageId")]
public virtual Stage Stage { get; set; }
public int StageId { get; set; }
To my Side class, I see StageId column added to my Side table.
This is working, but now throughout my application, any reference to Stage contains a SideId, which is in some cases totally irrelevant. I'd like to just give my Card and Side entities a Stage property based on the above Stage class without polluting the stage class with reference properties if possible... what am I doing wrong?
Because Stage is required, all one-to-many relationships where Stage is involved will have cascading delete enabled by default. It means, if you delete a Stage entity
the delete will cascade directly to Side
the delete will cascade directly to Card and because Card and Side have a required one-to-many relationship with cascading delete enabled by default again it will then cascade from Card to Side
So, you have two cascading delete paths from Stage to Side - which causes the exception.
You must either make the Stage optional in at least one of the entities (i.e. remove the [Required] attribute from the Stage properties) or disable cascading delete with Fluent API (not possible with data annotations):
modelBuilder.Entity<Card>()
.HasRequired(c => c.Stage)
.WithMany()
.WillCascadeOnDelete(false);
modelBuilder.Entity<Side>()
.HasRequired(s => s.Stage)
.WithMany()
.WillCascadeOnDelete(false);
I had a table that had a circular relationship with others and I was getting the same error. Turns out it is about the foreign key which was not nullable. If the key is not nullable the related object must be deleted, and circular relations don't allow that. So use nullable foreign key.
[ForeignKey("StageId")]
public virtual Stage Stage { get; set; }
public int? StageId { get; set; }
Anybody wondering how to do it in EF core:
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
foreach (var relationship in modelBuilder.Model.GetEntityTypes().SelectMany(e => e.GetForeignKeys()))
{
relationship.DeleteBehavior = DeleteBehavior.Restrict;
}
..... rest of the code.....
I was getting this error for lots of entities when I was migrating down from an EF7 model to an EF6 version. I didn't want to have to go through each entity one at a time, so I used:
builder.Conventions.Remove<ManyToManyCascadeDeleteConvention>();
builder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
You can set cascadeDelete to false or true (in your migration Up() method). Depends upon your requirement.
AddForeignKey("dbo.Stories", "StatusId", "dbo.Status", "StatusID", cascadeDelete: false);
In .NET Core I changed the onDelete option to ReferencialAction.NoAction
constraints: table =>
{
table.PrimaryKey("PK_Schedule", x => x.Id);
table.ForeignKey(
name: "FK_Schedule_Teams_HomeId",
column: x => x.HomeId,
principalTable: "Teams",
principalColumn: "Id",
onDelete: ReferentialAction.NoAction);
table.ForeignKey(
name: "FK_Schedule_Teams_VisitorId",
column: x => x.VisitorId,
principalTable: "Teams",
principalColumn: "Id",
onDelete: ReferentialAction.NoAction);
});
I had this issue also, I solved it instantly with this answer from a similar thread
In my case, I didn't want to delete the dependent record on key deletion. If this is the case in your situation just simply change the Boolean value in the migration to false:
AddForeignKey("dbo.Stories", "StatusId", "dbo.Status", "StatusID", cascadeDelete: false);
Chances are, if you are creating relationships which throw this compiler error but DO want to maintain cascade delete; you have an issue with your relationships.
I fixed this. When you add the migration, in the Up() method there will be a line like this:
.ForeignKey("dbo.Members", t => t.MemberId, cascadeDelete:True)
If you just delete the cascadeDelete from the end it will work.
Just for documentation purpose, to someone that comes on the future, this thing can be solved as simple as this, and with this method, you could do a method that disabled one time, and you could access your method normally
Add this method to the context database class:
protected override void OnModelCreating(DbModelBuilder modelBuilder) {
modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
}
In .NET Core I played with all upper answers - but without any success.
I made changes a lot in DB structure and every time added new migration attempting to update-database, but received the same error.
Then I started to remove-migration one by one until Package Manager Console threw me exception:
The migration '20170827183131_***' has already been applied to the database
After that, I added new migration (add-migration) and update-database successfully
So my suggestion would be: clear out all your temp migrations, until your current DB state.
public partial class recommended_books : DbMigration
{
public override void Up()
{
CreateTable(
"dbo.RecommendedBook",
c => new
{
RecommendedBookID = c.Int(nullable: false, identity: true),
CourseID = c.Int(nullable: false),
DepartmentID = c.Int(nullable: false),
Title = c.String(),
Author = c.String(),
PublicationDate = c.DateTime(nullable: false),
})
.PrimaryKey(t => t.RecommendedBookID)
.ForeignKey("dbo.Course", t => t.CourseID, cascadeDelete: false) // was true on migration
.ForeignKey("dbo.Department", t => t.DepartmentID, cascadeDelete: false) // was true on migration
.Index(t => t.CourseID)
.Index(t => t.DepartmentID);
}
public override void Down()
{
DropForeignKey("dbo.RecommendedBook", "DepartmentID", "dbo.Department");
DropForeignKey("dbo.RecommendedBook", "CourseID", "dbo.Course");
DropIndex("dbo.RecommendedBook", new[] { "DepartmentID" });
DropIndex("dbo.RecommendedBook", new[] { "CourseID" });
DropTable("dbo.RecommendedBook");
}
}
When your migration fails you are given a couple of options:
'Introducing FOREIGN KEY constraint 'FK_dbo.RecommendedBook_dbo.Department_DepartmentID' on table 'RecommendedBook' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints.
Could not create constraint or index. See previous errors.'
Here is an example of using the 'modify other FOREIGN KEY constraints' by setting 'cascadeDelete' to false in the migration file and then run 'update-database'.
Make your Foreign key attributes nullable. That will work.
This sounds weird and I don't know why, but in my case that was happening because my ConnectionString was using "." in "data source" attribute. Once I changed it to "localhost" it workded like a charm. No other change was needed.
The existing answers are great I just wanted to add that I ran into this error because of a different reason. I wanted to create an Initial EF migration on an existing DB but I didn't use the -IgnoreChanges flag and applied the Update-Database command on an empty Database (also on the existing fails).
Instead I had to run this command when the current db structure is the current one:
Add-Migration Initial -IgnoreChanges
There is likely a real problem in the db structure but save the world one step at a time...
In .NET 5 < and .NET Core 2.0 < you can use .OnDelete(DeleteBehavior.Restrict) in OnModelCreating like #Nexus23 answer but you do not need to disable cascade for every model.
Example with join entity type configuration many-to-many:
internal class MyContext : DbContext
{
public MyContext(DbContextOptions<MyContext> options)
: base(options)
{
}
public DbSet<Post> Posts { get; set; }
public DbSet<Tag> Tags { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Post>()
.HasMany(p => p.Tags)
.WithMany(p => p.Posts)
.UsingEntity<PostTag>(
j => j
.HasOne(pt => pt.Tag)
.WithMany(t => t.PostTags)
.HasForeignKey(pt => pt.TagId)
.OnDelete(DeleteBehavior.Restrict),
j => j
.HasOne(pt => pt.Post)
.WithMany(p => p.PostTags)
.HasForeignKey(pt => pt.PostId)
.OnDelete(DeleteBehavior.Restrict),
j =>
{
j.Property(pt => pt.PublicationDate).HasDefaultValueSql("CURRENT_TIMESTAMP");
j.HasKey(t => new { t.PostId, t.TagId });
});
}
}
public class Post
{
public int PostId { get; set; }
public string Title { get; set; }
public string Content { get; set; }
public ICollection<Tag> Tags { get; set; }
public List<PostTag> PostTags { get; set; }
}
public class Tag
{
public string TagId { get; set; }
public ICollection<Post> Posts { get; set; }
public List<PostTag> PostTags { get; set; }
}
public class PostTag
{
public DateTime PublicationDate { get; set; }
public int PostId { get; set; }
public Post Post { get; set; }
public string TagId { get; set; }
public Tag Tag { get; set; }
}
Sources:
https://learn.microsoft.com/en-us/ef/core/modeling/relationships?tabs=fluent-api%2Cfluent-api-simple-key%2Csimple-key#join-entity-type-configuration
https://learn.microsoft.com/en-us/dotnet/api/microsoft.entityframeworkcore.deletebehavior?view=efcore-5.0
This does require you to remove the many to many relationship yourself or you will receive the following error when you remove a parent entity:
The association between entity types '' and '' has been severed, but
the relationship is either marked as required or is implicitly
required because the foreign key is not nullable. If the
dependent/child entity should be deleted when a required relationship
is severed, configure the relationship to use cascade deletes.
Consider using 'DbContextOptionsBuilder.EnableSensitiveDataLogging' to
see the key values
You can solve this by using DeleteBehavior.ClientCascade instead which will allow EF to perform cascade deletes on loaded entities.
internal class MyContext : DbContext
{
public MyContext(DbContextOptions<MyContext> options)
: base(options)
{
}
public DbSet<Post> Posts { get; set; }
public DbSet<Tag> Tags { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Post>()
.HasMany(p => p.Tags)
.WithMany(p => p.Posts)
.UsingEntity<PostTag>(
j => j
.HasOne(pt => pt.Tag)
.WithMany(t => t.PostTags)
.HasForeignKey(pt => pt.TagId)
.OnDelete(DeleteBehavior.Cascade),
j => j
.HasOne(pt => pt.Post)
.WithMany(p => p.PostTags)
.HasForeignKey(pt => pt.PostId)
.OnDelete(DeleteBehavior.ClientCascade),
j =>
{
j.Property(pt => pt.PublicationDate).HasDefaultValueSql("CURRENT_TIMESTAMP");
j.HasKey(t => new { t.PostId, t.TagId });
});
}
}
public class Post
{
public int PostId { get; set; }
public string Title { get; set; }
public string Content { get; set; }
public ICollection<Tag> Tags { get; set; }
public List<PostTag> PostTags { get; set; }
}
public class Tag
{
public string TagId { get; set; }
public ICollection<Post> Posts { get; set; }
public List<PostTag> PostTags { get; set; }
}
public class PostTag
{
public DateTime PublicationDate { get; set; }
public int PostId { get; set; }
public Post Post { get; set; }
public string TagId { get; set; }
public Tag Tag { get; set; }
}
https://learn.microsoft.com/en-us/dotnet/api/microsoft.entityframeworkcore.deletebehavior?view=efcore-5.0
None of the aforementioned solutions worked for me. What I had to do was use a nullable int (int?) on the foreign key that was not required (or not a not null column key) and then delete some of my migrations.
Start by deleting the migrations, then try the nullable int.
Problem was both a modification and model design. No code change was necessary.
The simple way is to, Edit your migration file (cascadeDelete: true) into (cascadeDelete: false) then after assign the Update-Database command in your Package Manager Console.if it's problem with your last migration then all right. Otherwise check your earlier migration history, copy those things, paste into your last migration file, after that do it the same thing. it perfectly works for me.
You could add this in your DataContext.cs, this works for me...
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
modelBuilder.Conventions.Remove<ManyToManyCascadeDeleteConvention>();
}
I ran into the same problem and stuck for a long. The following steps saved me.
Go through the constraints and change the onDelete ReferentialAction to NoAction from Cascade
constraints: table =>
{
table.PrimaryKey("PK_table1", x => x.Id);
table.ForeignKey(
name: "FK_table1_table2_table2Id",
column: x => x.table2Id,
principalTable: "table2",
principalColumn: "Id",
onDelete: ReferentialAction.NoAction);
});
I am trying to create a new migration for my project and i just depared with an awkward situation... I have my aggregate root entity:
public class Classroom : Entity, IAggregateRoot
{
// PK
public int ClassroomId { get; set; }
// ....
public virtual ClassroomStreaming Streaming { get; set; }
}
And the aggregate:
public class ClassroomStreaming : Entity
{
// PK
public int ClassroomId { get; set; }
public virtual Classroom Classroom { get; set; }
// Fields
public string EmbedCode { get; set; }
// ...
}
The mappings are:
public class ClassroomMap : EntityTypeConfiguration<Classroom>
{
public ClassroomMap()
{
this.HasKey(t => t.ClassroomId);
this.ToTable("Classroom");
// ....
// One to One
this.HasOptional(t => t.Streaming)
.WithRequired(p => p.Classroom);
}
}
and:
public class ClassroomStreamingMap: EntityTypeConfiguration<ClassroomStreaming>
{
public ClassroomStreamingMap()
{
// Primary Key
this.HasKey(t => new { t.ClassroomId });
// Table & Column Mappings
this.ToTable("ClassroomStreaming");
this.Property(t => t.ClassroomId)
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
// Relationships
this.HasRequired(t => t.Classroom)
.WithOptional(p => p.Streaming)
.WillCascadeOnDelete(true);
}
}
When I generate the migration, i get the following situation where it creates the PK and also an non clustered index for the same column:
public override void Up()
{
CreateTable(
"dbo.ClassroomStreaming",
c => new
{
ClassroomId = c.Int(nullable: false),
// ....
})
.PrimaryKey(t => t.ClassroomId)
.ForeignKey("dbo.Classroom", t => t.ClassroomId, cascadeDelete: true)
.Index(t => t.ClassroomId);
}
Is it a normal behavior? look how it is in the SQL Server:
It looks like based you have "double-mapped" your relationships in the two EntityTypeConfiguration<T> classes. I think you only need to define the relationship in one direction.
The Entity Framework Fluent API documentation states that for one-to-zero-or-one relationships, define it with .HasOptional().WithRequired() as you have done in the ClassroomMap. You should be able remove the .HasRequired().WithOptional() in the ClassroomStreamingMap class.
I have something like this
public class AppointmentReminder
{
public virtual int ReminderId { get; private set; }
public virtual CalendarAppointment CalendarAppointment { get; set; }
}
public class CalendarAppointment
{
public virtual int AppointmentId { get; private set; }
public virtual IList<AppointmentReminder> AppointmentReminders { get; set; }
public CalendarAppointment()
{
AppointmentReminders = new List<AppointmentReminder>();
}
}
public class AppointmentReminderMap : ClassMap<AppointmentReminder>
{
public AppointmentReminderMap()
{
Table("AppointmentReminders");
Id(x => x.ReminderId);
References(x => x.CalendarAppointment).ForeignKey("AppointmentId").Column("AppointmentId").Not.Nullable();
}
}
public class CalendarAppointmentMap : ClassMap<CalendarAppointment>
{
public CalendarAppointmentMap()
{
Table("CalendarAppointments");
Id(x => x.AppointmentId);
HasMany(x => x.AppointmentReminders);
}
}
As you can see I try to tell AppointmentReminderMap what the name of the fk is by trying ForiegnKey and Column yet when I get this error
Server Error in '/' Application.
Invalid column name 'CalendarAppointmentId'.
Invalid column name 'CalendarAppointmentId'.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: Invalid column name 'CalendarAppointmentId'.
Invalid column name 'CalendarAppointmentId'.
Source Error:
It looking for CalendarAppointmentId. I don't why it repeats it twice. So I let fluent nhibernate generate my database to see what was going on. When I look at the appointmentReminder table it has a fk of CalendarAppointmentId.
Why does it not use the name that I specified?
Here is my config
public ISessionFactory GetSessionFactory()
{
ISessionFactory fluentConfiguration = Fluently.Configure()
.Database(MsSqlConfiguration.MsSql2008.ConnectionString(c => c.FromConnectionStringWithKey("ConnectionString")))
.Mappings(m => m.FluentMappings.AddFromAssemblyOf<Framework.Data.Mapping.MyMap>().Conventions.Add(ForeignKey.EndsWith("Id")))
//.ExposeConfiguration(BuidSchema)
.BuildSessionFactory();
return fluentConfiguration;
}
private static void BuidSchema(NHibernate.Cfg.Configuration config)
{
new NHibernate.Tool.hbm2ddl.SchemaExport(config).Create(false, true);
}
Try:
HasMany(x => x.AppointmentReminders).KeyColumn("AppointmentId");
ForeignKey is the name of the fk constraint, not the column. You probably need to make sure the HasMany is using the same column name..."AppointmentId". That convention you're using is making it default to CalendarAppointmentId which conflicts with what you've specified on the one-to-many side. So..another option would be to remove the Column("AppointmentId") on the one-to-many and let the convention do it's thing.
How do you do a 1 to 1 relationship with fluent nhibernate? I am using ms sql server 2008 and every time I looked the db tables through the database diagram viewer the table that should have one to one relationships don't seem to have them.
Users
UserId <pk> Guid
Settings
UserId <pk> Guid
public Settings
{
public virtual Guid UserId {get; private set;}
public virtual Setting User { get; set; }
}
public User
{
public virtual Guid UserId {get; private set;}
public virtual Setting Setting { get; set; }
}
public class UserMap : ClassMap<User>
{
Id(x => x.UserId);
HasOne(x => x.Setting);
}
public class SettingMap : ClassMap<Setting>
{
Id(x => x.UserId);
HasOne(x => x.User);
}
So I tried this but it did not work.
Why do you have a property of type Setting on your Setting class? It's called User so I would expect it (also because of your description of the problem) that it be a User class instead.
I had a similar problem, couldnt see any relationships being generated. I finally found that this worked:
public class ParentMap : ClassMap<Parent>
{
public ParentMap()
{
Id(x => x.Id);
HasOne(s => s.Child).Cascade.All();
}
}
public class ChildMap : ClassMap<Model.Child>
{
public ChildMap()
{
Id(x => x.Id);
HasOne(s => s.Parent).Constrained().ForeignKey();
}
}