Situation
I have searched for the answer to this extensively (on SO and elsewhere) and I am aware that there are many questions on SO by this same title.
I had a table mapping and model that were working. Then the schema was changed (I do not have direct control of the DB) such that a new Primary Key was introduced and the old Primary Key became the Foreign Key to another table. I believe this is the heart of the problem as no other entities seem to have issues
Mapping
Here is the method that maps my entity (called from OnModelCreating)
private static void MapThing(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Thing>().ToTable("ThingTable");
modelBuilder.Entity<Thing>().HasKey(p => p.Id);
modelBuilder.Entity<Thing>().Property(p => p.Id).HasColumnName("NewId");
modelBuilder.Entity<Thing>().Property(p => p.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
modelBuilder.Entity<Thing>().Property(p => p.FileName).HasColumnName("ColumnWhosNameChanged");
modelBuilder.Entity<Thing>().HasRequired(p => p.MetaDataOnThing);
}
The old PK of the table is now defined as a property on the model and it is the same name as the column (the reason it is not defined in the mapping above).
Model
Here is the Model (I have applied names that I hope will make it more clear what has changed):
public class Thing
{
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
//This used to be the PK, its names (Property AND Column) have not changed
public int OldId { get; set; }
//The column name for FileName changed to something else
public string FileName { get; set; }
//Unchanged
public byte[] Document { get; set; }
public string ContentType { get; set; }
//Navigation Property
public ThingMetaData MetaDataOnThing { get; set; }
}
Integration test
I removed a lot of structure to, hopefully, make it clear..the test is pretty straight forward
[TestMethod]
public void ThenThingWillBePersisted()
{
var thing = new Thing()
{
OldId = metaDataObject.Id,
Document = new byte[] { 42 },
FileName = "foo.jpg",
ContentType = "image/jpeg"
};
context.Things.Add(thing);
context.SaveChanges();
}
This test produces the error "A dependent property in a ReferentialConstraint is mapped to a store-generated column. Column:'NewId'" and the inner exception points to the NewId as being the issue. It does so on the SaveChanges() call.
Admittedly, I have a lot more experience with nHibernate than I do with Entity Framework but I am pretty sure my mappings and model are setup properly.
Has anyone seen this issue and how did you solve it?
Related
I am working on .NET CORE 6 along with EF CORE 7. I need to seed data in joining table but unable to do so and get error.
I am seed FileTypeId but not sure why EF core migration throwing error...
error
The seed entity for entity type 'JobFileType' cannot be added because it has the navigation 'FileType' set. To seed relationships, add the entity seed to 'JobFileType' and specify the foreign key values {'FileTypeId'}. Consider using 'DbContextOptionsBuilder.EnableSensitiveDataLogging' to see the involved property values.
ClassA
public class JobProfile
{
public JobProfile()
{
this.JobFileTypes = new HashSet<JobFileType>();
}
public Guid JobProfileId { get; set; }
public string Name { get; set; }
public ICollection<JobFileType>? JobFileTypes { get; set; }
}
ClassB
public class FileType
{
public FileType()
{
this.JobFileTypes = new HashSet<JobFileType>();
}
public Guid FileTypeId { get; set; }
public string Extension { get; set; } = string.Empty;
public ICollection<JobFileType>? JobFileTypes { get; set; }
}
Joing Table
public class JobFileType
{
public Guid JobFileTypeId { get; set; }
public Guid JobProfileId { get; set; }
public JobProfile JobProfile { get; set; } = new JobProfile();
public Guid FileTypeId { get; set; }
public FileType FileType { get; set; } = new FileType();
}
Seed Extension
public static class JobFileTypeSeed
{
public static void Seed(this ModelBuilder modelBuilder)
{
modelBuilder.Entity<JobFileType>()
.HasData(
new JobFileType {JobFileTypeId = Guid.Parse("aaa"), JobProfileId = Guid.Parse("ccc"), FileTypeId = Guid.Parse("yyy") },
new JobFileType { JobFileTypeId = Guid.Parse("bbb"), JobProfileId = Guid.Parse("ccc"), FileTypeId = Guid.Parse("zzz") }
);
}
}
config
internal class JobFileTypeConfiguration : IEntityTypeConfiguration<JobFileType>
{
public void Configure(EntityTypeBuilder<JobFileType> builder)
{
builder.ToTable("JobFileType", "dbo");
builder.HasKey(column => column.JobFileTypeId);
builder
.HasOne(jobFileType => jobFileType.JobProfile)
.WithMany(jobProfile => jobProfile.JobFileTypes)
.HasForeignKey(jobFileType => jobFileType.JobProfileId);
builder
.HasOne(jobFileType => jobFileType.FileType)
.WithMany(fileType => fileType.JobFileTypes)
.HasForeignKey(jobFileType => jobFileType.FileTypeId);
}
}
There is not much to say about the concrete issue (which btw is not specific to joining entity, but any entity model seeding):
I am seed FileTypeId but not sure why EF core migration throwing error...
as the cause of the issue is included at the beginning of the error message:
because it has the navigation 'FileType' set.
And your entity has
public FileType FileType { get; set; } = new FileType();
// ^ ^ ^
// the problem
and the same for
public JobProfile JobProfile { get; set; } = new JobProfile();
which will be the next error if you resolve the original.
Remove both navigation property initializers (= new ...) and the problem will be gone.
As a general rule, you should never initialize reference navigation properties because it causes many side effects and/or improper behaviors (not only for seeding, but also eager/lazy/explicit data loading). Initializing collection navigation properties is arbitrary, but ok. Only reference navigation property initialization must be avoided. For more info, see EF codefirst : Should I initialize navigation properties? - quite old EF topic, but still applies.
If you are trying to resolve NRT warnings (as I guess), initializing with new is definitely not a proper way. One reason I don't like NRT is because it is forcing people to use "workarounds" for preventing compiler warnings, which in fact break the primary functionality. Specifically in EF Core, enabling NRT also changes the optional/required attribute of some properties, hence database column types (most noticeable for string properties/columns and reference navigations). You could read more about this in the Working with Nullable Reference Types topic in the official EF Core documentation, but in general I would just disable NRT for EF entity model classes.
The proper order is to set the "master data" first and then try to set the join table, as you would expect.
The defaulting
{get;set;} = new Something();
Could be the offending declaration, since any instance upon creation will have the relation JobFileType already set
I'm trying to fetch (in disconnected way) an entity with its all related entities and then trying to update the entity. But I'm getting the following error:
Attaching an entity of type 'Feature' failed because another entity of the same type already has the same primary key value.
public class Person
{
public int PersonId { get; set; }
public string Personname { get; set }
public ICollection Addresses { get; set; }
}
public class Address
{
public int AddressId { get; set; }
public int PersonId { get; set; }
public string Line1 { get; set; }
public string City { get; set; }
public string State { get; set; }
public Person Person { get; set; }
public ICollection<Feature> Features { get; set; }
}
// Many to Many: Represented in database as AddressFeature (e.g Air Conditioning, Central Heating; User could select multiple features of a single address)
public class Feature
{
public int FeatureId { get; set; }
public string Featurename { get; set; }
public ICollection<Address> Addresses { get; set; } // Many-To-Many with Addresses
}
public Person GetCandidate(int id)
{
using (MyDbContext dbContext = new MyDbContext())
{
var person = dbContext.People.AsNoTracking().Where(x => x.PersonId == id);
person = person.Include(prop => prop.Addresses.Select(x => x.Country)).Include(prop => prop.Addresses.Select(x => x.Features));
return person.FirstOrDefault();
}
}
public void UpdateCandidate(Person newPerson)
{
Person existingPerson = GetPerson(person.Id); // Loading the existing candidate from database with ASNOTRACKING
dbContext.People.Attach(existingPerson); // This line is giving error
.....
.....
.....
}
Error:
Additional information: Attaching an entity of type 'Feature' failed because another entity of the same type already has the same primary key value.
It seems like (I may be wrong) GetCandidate is assigning every Feature within Person.Addresses a new instance. So, how could I modify the GetCandidate to make sure that the same instance (for same values) is bing assisgned to Person.Addresses --> Features.
Kindly suggest.
It seems like (I may be wrong) GetCandidate is assigning every Feature within Person.Addresses a new instance. So, how could I modify the GetCandidate to make sure that the same instance (for same values) is bing assisgned to Person.Addresses --> Features.
Since you are using a short lived DbContext for retrieving the data, all you need is to remove AsNoTracking(), thus allowing EF to use the context cache and consolidate the Feature entities. EF tracking serves different purposes. One is to allow consolidating the entity instances with the same PK which you are interested in this case, and the second is to detect the modifications in case you modify the entities and call SaveChanges(), which apparently you are not interested when using the context simply to retrieve the data. When you disable the tracking for a query, EF cannot use the cache, thus generates separate object instances.
What you really not want is to let EF create proxies which hold reference to the context used to obtain them and will cause issues when trying to attach to another context. I don't see virtual navigation properties in your models, so most likely EF will not create proxies, but in order to be absolutely sure, I would turn ProxyCreationEnabled off:
public Person GetCandidate(int id)
{
using (MyDbContext dbContext = new MyDbContext())
{
dbContext.Configuration.ProxyCreationEnabled = false;
var person = dbContext.People.Where(x => x.PersonId == id);
person = person.Include(prop => prop.Addresses.Select(x => x.Country)).Include(prop => prop.Addresses.Select(x => x.Features));
return person.FirstOrDefault();
}
}
How to configure a EF6 migration with a model class having?
A collection o items
A navigation property to one particular item
public class MyModel
{
[Key]
public int Id { get; set; }
// My collection of elements
public virtual ICollection<MyCollectionElement> MyCollection { get; set; }
// Optional navigation to a particular element from the collection
[ForeignKey("CurrentElement")]
public int? CurrentElementId { get; set; }
public virtual MyCollectionElement CurrentElement { get; set; }
}
public class MyCollectionElement
{
[Key]
public int Id { get; set; }
// Required navigation to MyClass
[ForeignKey("MyModel")]
public int MyModelID { get; set; }
public virtual MyModel Model { get; set; }
}
Configuration
modelBuilder.Entity<MyModel>()
.HasMany(x => x.MyCollection)
.WithRequired(x => x.Model)
.HasForeignKey(x => x.MyModelID)
.WillCascadadeOnDelete(false);
Throws several errors on Update-Database, like
Unable to determine a valid ordering for dependent operations.
I would like a solution which doesn't involve a boolean IsCurrent in MyCollectionElement to make another query later and find which element is the current; instead, I would like to store the current element's id with my model, like exposed.
Also, I don't mind making int CurrentElementId non nullable (required) if it's easier.
Thanks.
This chicken-and-egg problem always looms when there are circular relationships. The error...
Unable to determine a valid ordering for dependent operations.
...is not thrown when the database is created. The database can be created just fine. It occurs when you try to insert a MyModel record and a MyCollectionElement referring to one another in the same unit of work. In the Seed method you probably have something like
var element = new MyCollectionElement();
var model = new MyModel();
model.MyCollection.Add(element);
model.CurrentElement = element;
The statement model.MyCollection.Add(element); requires model to be inserted first, so element can refer to it in its foreign key. But model.CurrentElement = element; requires element to be inserted first.
You can only avoid this situation by calling SaveChanges twice, and wrapping everything in a TransactionScope if you want the assignments to be transactional:
using(var ts = new TransactionScope())
{
using(var db = new MyContext()
{
var element = new MyCollectionElement();
var model = new MyModel();
model.MyCollection.Add(element);
db.MyModels.Add(model);
db.SaveChanges();
model.CurrentElement = element;
db.SaveChanges();
}
ts.Complete();
}
This also means that int CurrentElementId should remain nullable.
I have a trouble with EF (6.1.3)
I have created next classes (with many-to-many relationship):
public class Record
{
[Key]
public int RecordId { get; set; }
[Required]
public string Text { get; set; }
public virtual ICollection<Tag> Tags { get; set; }
}
public class Tag
{
[Key]
public int TagId { get; set; }
[Required]
public string Name { get; set; }
public virtual ICollection<Record> Records{ get; set; }
}
And method:
void AddTags()
{
Record[] records;
Tag[] tags;
using (var context = new AppDbContext())
{
records = context.Records.ToArray();
}//remove line to fix
tags = Enumerable.Range(0, 5).Select(x => new Tag()
{
Name = string.Format("Tag_{0}", x),
Records= records.Skip(x * 5).Take(5).ToArray()
}).ToArray();
using (var context = new AppDbContext()){ //remove line to fix
context.Tags.AddRange(tags);
context.SaveChanges();
}
}
If I use two contexts, the records (which were added to created tags) will be duplicated. If I remove marked rows - problem disappears.
Is there any way to fix this problem without using the same context?
If you can, better reload entities or not detach them at all. Using multiple context instances in application is overall making things much more complicated.
The problem for you comes from the Entity Framework entity change tracker. When you load entitites from your DbContext and dispose that context, entities get detached from entity change tracker, and Entity Framework has no knowledge of any changes made to it.
After you reference detached entity by an attached entity, it (detached entity) immediately gets into entity change tracker, and it has no idea that this entity was loaded before. To give Entity Framework an idea that this detached entity comes from the database, you have to reattach it:
foreach (var record in records) {
dbContext.Entry(record).State = EntityState.Unchanged;
}
This way you will be able to use records to reference in other objects, but if you have any changes made to these records, then all these changes will go away. To make changes apply to database you have to change state to Added:
dbContext.Entry(record).State = EntityState.Modified;
Entity Framework uses your mappings to determine row in database to apply changes to, specifically using your Primary Key settings.
A couple examples:
public class Bird
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
public string Color { get; set; }
}
public class Tree
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
}
public class BirdOnATree
{
[Column(Order = 0), Key, ForeignKey("Bird")]
public int BirdId { get; set; }
public Bird Bird { get; set; }
[Column(Order = 1), Key, ForeignKey("Tree")]
public int TreeId { get; set; }
public Tree Tree { get; set; }
public DateTime SittingSessionStartedAt { get; set; }
}
Here's a small entity structure so that you could see how it works. You can see that Bird and Tree have simple Key - Id. BirdOnATree is a many-to-many table for Bird-Tree pair with additional column SittingSessionStartedAt.
Here's the code for multiple contexts:
Bird bird;
using (var context = new TestDbContext())
{
bird = context.Birds.First();
}
using (var context = new TestDbContext())
{
var tree = context.Trees.First();
var newBirdOnAtree = context.BirdsOnTrees.Create();
newBirdOnAtree.Bird = bird;
newBirdOnAtree.Tree = tree;
newBirdOnAtree.SittingSessionStartedAt = DateTime.UtcNow;
context.BirdsOnTrees.Add(newBirdOnAtree);
context.SaveChanges();
}
In this case, bird was detached from the DB and not attached again. Entity Framework will account this entity as a new entity, which never existed in DB, even though Id property is set to point to existing row to database. To change this you just add this line to second DbContext right in the beginning:
context.Entry(bird).State = EntityState.Unchanged;
If this code is executed, it will not create new Bird entity in DB, but use existing instead.
Second example: instead of getting bird from the database, we create it by ourselves:
bird = new Bird
{
Id = 1,
Name = "Nightingale",
Color = "Gray"
}; // these data are different in DB
When executed, this code will also not create another bird entity, will make a reference to bird with Id = 1 in BirdOnATree table, and will not update bird entity with Id = 1. In fact you can put any data here, just use correct Id.
If we change our code here to make this detached entity update existing row in DB:
context.Entry(bird).State = EntityState.Modified;
This way, correct data will be inserted to table BirdOnATree, but also row with Id = 1 will be updated in table Bird to fit the data you provided in the application.
You can check this article about object state tracking:
https://msdn.microsoft.com/en-US/library/dd456848(v=vs.100).aspx
Overall, if you can avoid this, don't use object state tracking and related code. It might come to unwanted changes that are hard to find source for - fields are updated for entity when you don't expect them to, or are not updated when you expect it.
I have a table in my database called SEntries (see below the CREATE TABLE statement). It has a primary key, a couple of foreign keys and nothing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF Proxy Class.
This is how the class is declared in C#:
public class SEntry
{
public long SEntryId { get; set; }
public long OriginatorId { get; set; }
public DateTime DatePosted { get; set; }
public string Message { get; set; }
public byte DataEntrySource { get; set; }
public string SourceLink { get; set; }
public int SourceAppId { get; set; }
public int? LocationId { get; set; }
public long? ActivityId { get; set; }
public short OriginatorObjectTypeId { get; set; }
}
public class EMData : DbContext
{
public DbSet<SEntry> SEntries { get; set; }
...
}
When I try to add a new row to that table, I get the error:
System.Data.SqlClient.SqlException: Invalid column name 'Discriminator'.
This problem only occurs if you are inheriting your C# class from another class, but SEntry is not inheriting from anything (as you can see above).
In addition to that, once I get the tool-tip on the debugger when I mouse over the EMData instance for the SEntries property, it displays:
base {System.Data.Entity.Infrastructure.DbQuery<EM.SEntry>} = {SELECT
[Extent1].[Discriminator] AS [Discriminator],
[Extent1].[SEntryId] AS [SEntryId],
[Extent1].[OriginatorId] AS [OriginatorId],
[Extent1].[DatePosted] AS [DatePosted],
[Extent1].[Message] AS [Message],
[Extent1].[DataEntrySource] AS [DataE...
Any suggestions or ideas where to get to the bottom of this issue? I tried renaming the table, the primary key and a few other things, but nothing works.
SQL-Table:
CREATE TABLE [dbo].[SEntries](
[SEntryId] [bigint] IDENTITY(1125899906842624,1) NOT NULL,
[OriginatorId] [bigint] NOT NULL,
[DatePosted] [datetime] NOT NULL,
[Message] [nvarchar](500) NOT NULL,
[DataEntrySource] [tinyint] NOT NULL,
[SourceLink] [nvarchar](100) NULL,
[SourceAppId] [int] NOT NULL,
[LocationId] [int] NULL,
[ActivityId] [bigint] NULL,
[OriginatorObjectTypeId] [smallint] NOT NULL,
CONSTRAINT [PK_SEntries] PRIMARY KEY CLUSTERED
(
[SEntryId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[SEntries] WITH CHECK ADD CONSTRAINT [FK_SEntries_ObjectTypes] FOREIGN KEY([OriginatorObjectTypeId])
REFERENCES [dbo].[ObjectTypes] ([ObjectTypeId])
GO
ALTER TABLE [dbo].[SEntries] CHECK CONSTRAINT [FK_SEntries_ObjectTypes]
GO
ALTER TABLE [dbo].[SEntries] WITH CHECK ADD CONSTRAINT [FK_SEntries_SourceApps] FOREIGN KEY([SourceAppId])
REFERENCES [dbo].[SourceApps] ([SourceAppId])
GO
ALTER TABLE [dbo].[SEntries] CHECK CONSTRAINT [FK_SEntries_SourceApps]
GO
Turns out that Entity Framework will assume that any class that inherits from a POCO class that is mapped to a table on the database requires a Discriminator column, even if the derived class will not be saved to the DB.
The solution is quite simple and you just need to add [NotMapped] as an attribute of the derived class.
Example:
class Person
{
public string Name { get; set; }
}
[NotMapped]
class PersonViewModel : Person
{
public bool UpdateProfile { get; set; }
}
Now, even if you map the Person class to the Person table on the database, a "Discriminator" column will not be created because the derived class has [NotMapped].
As an additional tip, you can use [NotMapped] to properties you don't want to map to a field on the DB.
Here is the Fluent API syntax.
http://blogs.msdn.com/b/adonet/archive/2010/12/06/ef-feature-ctp5-fluent-api-samples.aspx
class Person
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string FullName {
get {
return this.FirstName + " " + this.LastName;
}
}
}
class PersonViewModel : Person
{
public bool UpdateProfile { get; set; }
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
// ignore a type that is not mapped to a database table
modelBuilder.Ignore<PersonViewModel>();
// ignore a property that is not mapped to a database column
modelBuilder.Entity<Person>()
.Ignore(p => p.FullName);
}
I just encountered this and my problem was caused by having two entities both with the System.ComponentModel.DataAnnotations.Schema.TableAttribute referring to the same table.
for example:
[Table("foo")]
public class foo
{
// some stuff here
}
[Table("foo")]
public class fooExtended
{
// more stuff here
}
changing the second one from foo to foo_extended fixed this for me and I'm now using Table Per Type (TPT)
I had a similar problem, not exactly the same conditions and then i saw this post. Hope it helps someone. Apparently i was using one of my EF entity models a base class for a type that was not specified as a db set in my dbcontext. To fix this issue i had to create a base class that had all the properties common to the two types and inherit from the new base class among the two types.
Example:
//Bad Flow
//class defined in dbcontext as a dbset
public class Customer{
public int Id {get; set;}
public string Name {get; set;}
}
//class not defined in dbcontext as a dbset
public class DuplicateCustomer:Customer{
public object DuplicateId {get; set;}
}
//Good/Correct flow*
//Common base class
public class CustomerBase{
public int Id {get; set;}
public string Name {get; set;}
}
//entity model referenced in dbcontext as a dbset
public class Customer: CustomerBase{
}
//entity model not referenced in dbcontext as a dbset
public class DuplicateCustomer:CustomerBase{
public object DuplicateId {get; set;}
}
Another scenario where this occurs is when you have a base class and one or more subclasses, where at least one of the subclasses introduce extra properties:
class Folder {
[key]
public string Id { get; set; }
public string Name { get; set; }
}
// Adds no props, but comes from a different view in the db to Folder:
class SomeKindOfFolder: Folder {
}
// Adds some props, but comes from a different view in the db to Folder:
class AnotherKindOfFolder: Folder {
public string FolderAttributes { get; set; }
}
If these are mapped in the DbContext like below, the "'Invalid column name 'Discriminator'" error occurs when any type based on Folder base type is accessed:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Folder>().ToTable("All_Folders");
modelBuilder.Entity<SomeKindOfFolder>().ToTable("Some_Kind_Of_Folders");
modelBuilder.Entity<AnotherKindOfFolder>().ToTable("Another_Kind_Of_Folders");
}
I found that to fix the issue, we extract the props of Folder to a base class (which is not mapped in OnModelCreating()) like so - OnModelCreating should be unchanged:
class FolderBase {
[key]
public string Id { get; set; }
public string Name { get; set; }
}
class Folder: FolderBase {
}
class SomeKindOfFolder: FolderBase {
}
class AnotherKindOfFolder: FolderBase {
public string FolderAttributes { get; set; }
}
This eliminates the issue, but I don't know why!
I get the error in another situation, and here are the problem and the solution:
I have 2 classes derived from a same base class named LevledItem:
public partial class Team : LeveledItem
{
//Everything is ok here!
}
public partial class Story : LeveledItem
{
//Everything is ok here!
}
But in their DbContext, I copied some code but forget to change one of the class name:
public class MFCTeamDbContext : DbContext
{
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
//Other codes here
modelBuilder.Entity<LeveledItem>()
.Map<Team>(m => m.Requires("Type").HasValue(ItemType.Team));
}
public class ProductBacklogDbContext : DbContext
{
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
//Other codes here
modelBuilder.Entity<LeveledItem>()
.Map<Team>(m => m.Requires("Type").HasValue(ItemType.Story));
}
Yes, the second Map< Team> should be Map< Story>.
And it cost me half a day to figure it out!
Old Q, but for posterity...it also also happens (.NET Core 2.1) if you have a self-referencing navigation property ("Parent" or "Children" of the same type) but the Id property name isn't what EF expects. That is, I had an "Id" property on my class called WorkflowBase, and it had an array of related child steps, which were also of type WorkflowBase, and it kept trying to associate them with a non-existent "WorkflowBaseId" (the name i suppose it prefers as a natural/conventional default). I had to explicitly configure it using HasMany(), WithOne(), and HasConstraintName() to tell it how to traverse. But I spent a few hours thinking the problem was in 'locally' mapping the object's primary key, which i attempted to fix a bunch of different ways but which was probably always working.
this error happen with me because I did the following
I changed Column name of table in database
(I did not used Update Model from database in Edmx) I Renamed manually Property name to match the change in database schema
I did some refactoring to change name of the property in the class to be the same as database schema and models in Edmx
Although all of this, I got this error
so what to do
I Deleted the model from Edmx
Right Click and Update Model from database
this will regenerate the model, and entity framework will not give you this error
hope this help you