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Entity Framework invalid object name "dbo.EA_EmployeePerformance"

It is weird since I use the simple membership initialization my EF model cannot create a new table. My code was able to create the new table needed if there is a transaction required for the model.
This is my model :
public class EmployeeDBContext : DbContext
{
public EmployeeDBContext()
: base("DefaultConnection")
{
Database.SetInitializer<EmployeeDBContext>(new CreateDatabaseIfNotExists<EmployeeDBContext>());
}
public DbSet<EA_Employee> Employees { get; set; }
public DbSet<EA_EmployeePerformance> EmployeePerformances { get; set; }
public DbSet<EA_EmployeeRank> EmployeeRanks { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
}
}
[Table("EA_EmployeePerformance")]
public class EA_EmployeePerformance
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
[Display(Name = "Employee Performance Id")]
public int EmployeePerformanceId { get; set; }
[Index("Performance", IsUnique = true)]
[MaxLength(20)]
[Required]
public string Performance { get; set; }
public EA_EmployeePerformance()
{
Performance = "";
}
}
Whenever I SaveChanges(), the DB throws me
"Invalid object name dbo.EmployeePerformance".
I check the database and the database only contains tables required from simple membership.
How can I auto create the tables when a transaction is occurred for that model?
--------- EDITED ---------
Now I know what is my problem. The problem is because I use multiple dbContext in one database. It is gonna be tricky to do the migration because migration only works on one dbContext isn't it?
So in my case the problem is because the original AccountDBContext from the simple membership is taking over my database, that is why my other dbContext such as the EmployeeDBContext cannot create the new table (please correct me if i'm wrong).
Is there a way for me to keep the multiple dbContexts in a single database?

First you have to change your Db Initializer to DropCreateDatabaseIfModelChanges otherwise, you will still have the old database and you will never get the model changes without deleting the database manually.
database. It is gonna be tricky to do the migration because migration only works on one dbContext isn't it?
For migration I recommend you to create one DbContext for migration that called for Example MigrationDbContext which contains the the all DbSets and the POCO objects, also when the POCO objects belong to other assembly then just reference them.

Try using Migrations, this will help you manage your changes in your code and update the database scheme accordingly.
Here is a guide for how to use it Migrations.

Create a one to zero-or-one relation on a non-key field

We use Entity Framework 6 with CodeFirst and an Oracle.ManagedDataAccess.
I just created a 1 to 0..1 (one to zero or one) relation between two tables, and it works like a charm. But when adding a second relation, I got into trouble, because the original primary key column was demoted to just a data column, and a surrogate (sequence) primary key column was added. The foreign key constraint is still on the old field.
Code:
public class Node
{
[Key, Column("ID"), Required]
public int Id { get; set; }
[Column("POINT_CODE"), Required, StringLength(10)]
public string PointCode { get; set; }
// ...columns left out...
[ForeignKey("PointCode"), Required]
public NetworkPoint PointCodeFk { get; set; }
}
public class Point
{
[Key, Column("POINT_CODE"), Required, StringLength(10)]
public string PointCode { get; set; }
// ...columns left out...
[ForeignKey("PointCode")]
public Node NodeFk { get; set; }
}
public class MyDbContext : EntityContext
{
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Point>()
.HasOptional(m => m.NodeFk)
.WithRequired(o => o.PointCodeFk);
}
// ...stuff left out...
}
The difference with the working example is, the property Node.PointCode has the attribute Key, and there is no Node.Id column.
When running this example, I get the error message:
Multiplicity is not valid in Role 'Point_NodeFk_Target' in relationship 'Point_NodeFk'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
So I guess EntityFramework now thinks it should be an 1:N relation.
How can this be solved? I can't change the database (although I would like to very much).

Entity Framework requires a primary key on each table. You need to add a primary without which EF will complain. So looking at your code Point class require ID, Id ,PointId or PointID property so EF will know it has a primary key. Any of the conventions I showed here as a class property will be acceptable to EF.

Entity framework 6 foreign key is not being updated on attach and save

I have a issue with entity framework 6 not updating the foreign key when I try to update a entity object. It works on insert (but then I have to set the state to Unchanged for not to reinsert a new entity in the foreign key table). I am using code first approach and generated the models myself. It's a web application so the entity objects gets detached, so I have to reattach them.
I've created a simplified example so it's easy to explain what my problem is. In this example I have a car object which has a one to many relation to make. I want to update a car and change what make it is and its name. The name is updated but not the foreign key value. How do I go ahead to get the foreign key to be updated too?
The code handeling the attaching
public void UpdateCars(Car car){
var dbContext = new CarsDbContext(); //Inherits DbContext
dbContext.Cars.Attach(car);
dbContext.Entry(car).State = EntityState.Modified;
dbContext.SaveChanges();
}
The car Entity
[Table("Car")]
public class Car
{
public Guid Id { get; set; }
public String Name { get; set; }
public virtual Make Make { get; set; }
}
[Table("Make")]
public class Make
{
public Guid Id { get; set; }
public String Name { get; set; }
}
Edit:
I did a few more changes with help from comments (thanks guys!) and I made something work but it feels like I'm doing it the wrong way because the code is far from pretty. Here's what I did:
Modified the Car object to:
public String Name { get; set; }
public Guid Make_Id
[ForeignKey("Make_Id")]
public virtual Make Make { get; set; }
In my update
var dbContext = new CarsDbContext(); //Inherits DbContext
car.Make_Id = car.Make.Id;
dbContext.Cars.Attach(car);
There surely must be a better practice around this when doing EF code first when working with detached entities?

I ended up using graphdiff which solved all my problems. Also when my entities became more complex and it tried to attachs same entity several times. Here's a article to read about it: http://blog.brentmckendrick.com/introducing-graphdiff-for-entity-framework-code-first-allowing-automated-updates-of-a-graph-of-detached-entities/

Cascadable one-to-one, required:required relationship with EF

I have a Video class and a MediaContent class that are linked by a 1-1, required:required relationship: each Video must have exactly 1 associated MediaContent. Deleting a MediaContent object must result in the deletion of the associated Video object.
Using the fluent API, the relationship can be modeled as follows:
modelBuilder.Entity<Video.Video>()
.HasRequired(v => v.MediaContent).WithRequiredPrincipal(mc => mc.Video)
.WillCascadeOnDelete(true);
When adding a migration to reflect this change in the database, this is how the relationship gets transcribed in terms of foreign keys:
AddForeignKey("MediaContents", "MediaContentId", "Videos", "VideoId", cascadeDelete: true);
Updating the database, I get the following error:
Cascading foreign key 'FK_MediaContents_Videos_MediaContentId' cannot be created where the referencing column 'MediaContents.MediaContentId' is an identity column.
Dropping the WillCascadeOnDelete(true) property removes the error, but I'm not sure I understand why. Shouldn't the error appear whether or not cascading is turned on? The way I understand the problem, the error comes from the fact that the generation of VideoId and MediaContentId is handled by auto-increment (or by whatever the id generation strategy is), potentially contradicting the foreign key constraint. But I can't see what this has to do with delete-cascading...
What am I missing? More generally, how would you go about modeling a cascadable one-to-one, required:required relationship with EF?

I avoid the modelBuilder cruft approach and use simple POCOs and attributes generally - which you can use to accomplish your goals like so:
public class Video
{
public int Id { get; set; }
// Adding this doesn't change the db/schema, but it is enforced in code if
// you try to add a Video without a MediaContent.
[Required]
public MediaContent MediaContent { get; set; }
}
public class MediaContent
{
[ForeignKey("Video")]
public int Id { get; set; }
public Video Video { get; set;}
}

Unhandled Exception after Upgrading to Entity Framework 4.3.1

Error:
Unhandled Exception: System.Data.SqlClient.SqlException: The operation failed because an index or statistics with name 'IX_ID' already exists on table 'PrivateMakeUpLessons'.
Model (Simplified, building in a separate test project for debugging):
public abstract class Lesson
{
public Guid ID { get; set; }
public string Room { get; set; }
public TimeSpan Time { get; set; }
public int Duration { get; set; }
}
public abstract class RecurringLesson : Lesson
{
public int DayOfWeek { get; set; }
public DateTime StartDate { get; set; }
public DateTime EndDate { get; set; }
public string Frequency { get; set; }
}
public class PrivateLesson : RecurringLesson
{
public string Student { get; set; }
public string Teacher { get; set; }
public virtual ICollection<Cancellation> Cancellations { get; set; }
}
public class Cancellation
{
public Guid ID { get; set; }
public DateTime Date { get; set; }
public virtual PrivateLesson Lesson { get; set; }
public virtual MakeUpLesson MakeUpLesson { get; set; }
}
public class MakeUpLesson : Lesson
{
public DateTime Date { get; set; }
public string Teacher { get; set; }
public virtual Cancellation Cancellation { get; set; }
}
Configuration:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Lesson>().ToTable("Lessons");
modelBuilder.Entity<RecurringLesson>().ToTable("RecurringLessons");
modelBuilder.Entity<PrivateLesson>().ToTable("PrivateLessons");
modelBuilder.Entity<MakeUpLesson>().ToTable("PrivateMakeUpLessons");
modelBuilder.Entity<Cancellation>()
.HasOptional(x => x.MakeUpLesson)
.WithRequired(x => x.Cancellation);
base.OnModelCreating(modelBuilder);
}
Notes:
This worked fine in EF 4.2. Is there something wrong with my model? The actual model is much more complicated which is why I have all the classes abstracted out. Also, I am working against an existing database so I need to use Table-Per-Type inheritance.
If I change the relationship of Cancellation to PrivateMakeUpLesson from 1 to 0..1 to 0..1 to 0..1 it works. This is undesirable because you can't have a PrivateMakeUpLesson without a Cancellation.
Also, if I make PrivateMakeUpLesson NOT inherit from Lesson then it also works, but it IS a lesson and needs to remain so for existing business logic.
I'd appreciate any guidance. Thank you!
Edit:
Starting a bounty. I can't find any documentation on what changed between EF 4.2 and EF 4.3 with regard to the index generation for code first. It's clear that EF 4.3 is creating more indexes and that the naming scheme has changed but I want to know if there's a bug in EF or if there is something fundamentally wrong with my model or fluent API configuration.

As of EF 4.3, indexes are added for freign key columns during database creation. There is a bug that can cause an index to be created more than once. This will be fixed in a future EF release.
Until then, you can work around the issue by creating your database using Migrations instead of database initializers (or the Database.Create() method).
After generating the initial migration, you will need to delete the redundant call to Index().
CreateTable(
"dbo.PrivateMakeUpLessons",
c => new
{
ID = c.Guid(nullable: false),
...
})
.PrimaryKey(t => t.ID)
.ForeignKey("dbo.Lessons", t => t.ID)
.ForeignKey("dbo.Cancellations", t => t.ID)
.Index(t => t.ID)
.Index(t => t.ID); // <-- Remove this
To continue creating your database at run-time, you can use the MigrateDatabaseToLatestVersion initializer.

In my opinion this is clearly a bug.
The problem starts with the observation that EF creates an index IX_ID at all. If you strip down the model to the following...
public abstract class Lesson
{
public Guid ID { get; set; }
}
public class RecurringLesson : Lesson
{
}
public class MyContext : DbContext
{
public DbSet<Lesson> Lessons { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<RecurringLesson>().ToTable("RecurringLessons");
}
}
... and let EF create the database schema you get two tables Lessons and RecurringLessons as expected for a TPT inheritance mapping. But I am wondering why it creates two indices for the table RecurringLessons:
Index PK_RecurringLessons (clustered, unique) with Index column ID
Index IX_ID (not clustered, not unique) with Index column ID again
I don't know if there is any benefit for the database to have a second index on the same column. But for my understanding it doesn't make sense 1) to create an index on the same column that is already covered in the PK clustered index, and 2) to create a not unique index on a column which is the primary key and therefore necessarily unique.
Moreover due to the one-to-one relationship EF tries to create an index on the table of the dependent of this association which is PrivateMakeUpLessons. (It's the dependent (and not the principal) because Cancellation is required in entity MakeUpLesson.)
ID is the foreign key in this association (and primary key at the same time because one-to-one relationships are always shared primary key associations in Entity Framework). EF apparently always creates a index on the foreign key of a relationship. But for one-to-many relationships this is not a problem because the FK column is different from the PK column. Not so for one-to-one relatonships: The FK and PK are the same (that is ID), hence EF tries to create an index IX_ID for this one-to-one relationship which already exists due to the TPT inheritance mapping (which leads to a one-to-one relationship as well from database perspective).
The same consideration as above applies here: The table PrivateMakeUpLessons has a clustered PK index on column ID. Why is a second index IX_ID on the same column required at all?
In addition EF doesn't seem to check that it already wants to create an Index with name IX_ID for the TPT inheritance, leading finally to the exception in the database when the DDL is sent to create the database schema.
EF 4.2 (and before) didn't create any indices (except PK indices) at all, this was introduced in EF 4.3, especially indices for FK columns.
I didn't find a workaround. In the worst case you have to create the database schema manually and avoid that EF tries to create it (= disable database initialization). In the best case there is a way to disable automatic FK index creation, but I don't know if it's possible.
You can submit a bug report here: http://connect.microsoft.com/VisualStudio
Or maybe someone from EF development team will see your question here and provide a solution.

I got a very similar error to this one in my code a while back. Try putting the cancellation list inside the Lesson class. That's what solved my problem.

Below I describe 2 scenarios what is probably going wrong. Please read in depth by clicking the links I provided to know more about my explanation.
First
Lesson and RecurringLesson are abstract classes (so you want to have it as the base classes).
You are creating a table of the Lesson and the RecurringLesson entities which will result in a Table per hierarchy structure.
brief description
Creating a class of the base table will result in one big table which contains the columns of all inherited tables. So all properties of PrivateLesson, MakeUpLesson and all others inherited entities will be stored in the Lessons table. EF will add also a Discriminator column. The value of this column defaults to the persistent class name (like "PrivateLesson" or "MakeUpLesson") only the column matching to that particular entity (matching the Discriminator value) will be used in that particular row.
BUT
You are also mapping the inherited classes like PrivateLesson and MakeUpLesson. This will force EF to use the Table per Type structure which results in one table per class. This can cause conflicts you are facing right now.
Second
Your example shows you have an one-to-one relationship (Cancellation -> MakeUpLesson) and a one-to-many relationship (Cancellation -> PrivateLesson) because PrivateLesson and MakeUpLessonare both (indirect) inherited from Lesson in combination with the first described scenario can cause problems because it will result in 2 foreign key relationships in the database per entity. (one using Table per hierarchy structure and one using the Table per Type structure).
Also this post can help you defining a correct one-to-one definition.
Please verify by performing the following steps:
I assume you have your own test environment so you can create new test databases
1.
Delete the relationships to the Cancellation by commenting out all properties to this class:
public class PrivateLesson : RecurringLesson
{
public string Student { get; set; }
public string Teacher { get; set; }
//public virtual ICollection<Cancellation> Cancellations { get; set; }
}
public class Cancellation
{
public Guid ID { get; set; }
public DateTime Date { get; set; }
//public virtual PrivateLesson Lesson { get; set; }
//public virtual MakeUpLesson MakeUpLesson { get; set; }
}
public class MakeUpLesson : Lesson
{
public DateTime Date { get; set; }
public string Teacher { get; set; }
//public virtual Cancellation Cancellation { get; set; }
}
And remove the configuration to it:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Lesson>().ToTable("Lessons");
modelBuilder.Entity<RecurringLesson>().ToTable("RecurringLessons");
modelBuilder.Entity<PrivateLesson>().ToTable("PrivateLessons");
modelBuilder.Entity<MakeUpLesson>().ToTable("PrivateMakeUpLessons");
//modelBuilder.Entity<Cancellation>()
// .HasOptional(x => x.MakeUpLesson)
// .WithRequired(x => x.Cancellation);
base.OnModelCreating(modelBuilder);
}
2.
Create a new empty database
3.
Let EF generate the table structure for you in this empty database.
4.
Verify the first scenario. If that's true this need to be fixed first by using the Table per hierarchy structure OR the Table per Type structure. Probably you want to use the Table per hierarchy structure because (if I understand your question well) there is already an production environment.

When my project was updated from EF 6.0.2 to EF 6.1.1, I had such a problem, then back to 6.0.2, after the return of an older version, the error disappeared