I have two classes, here are the relevant bits:
public class Endorsement
{
public Guid? ContractId { get; set; }
public virtual Contract Contract { get; set; }
}
public class Contract
{
public virtual ICollection<Endorsement> Sales { get; set; }
}
The Endorsement class doesn't have a corresponding configuration, but the Contract class does:
public class ContractConfiguration : EntityTypeConfiguration<Contract>
{
public ContractConfiguration()
{
HasMany(a => a.Sales).WithRequired(a => a.Contract).HasForeignKey(a => a.ContractId);
}
}
I'm trying to change the Contract on an Endorsement to another Contract:
var endorsement = Context.Set<Endorsement>().Find(endorsementId);
var newContract = Context.Set<Contract>().Find(newContractId);
endorsement.Contract = newContract;
/* Instead of the line above, I have also tried endorsement.ContractId = newContract.Id;
I have also tried newContract.Sales.Add(endorsement); and then setting the state of
the newContract entry to modified and saving, all with the same results.
*/
var entry = Context.Entry(endorsement);
entry.State = EntityState.Modified;
Context.SaveChanges();
Context.SaveChanges(); throws the following exception:
The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: A referential integrity constraint violation occurred: The property value(s) of 'Contract.Id' on one end of a relationship do not match the property value(s) of 'Endorsement.ContractId' on the other end.
Any idea what's causing this?
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();
}
}
I have the following scenario: A case has a 1 to 0..1 relationship to an appointment (I always need a case to work on. This case does not need to have an appointment. But every appointment needs to have a case.) This is implemented as follows:
public class Case
{
[Key]
public long CaseId { get; set; }
public virtual Appointment Appointment { get; set; }
// ... and several other properties.
}
public class Appointment
{
[Key]
public long AppointmentId { get; set; }
public virtual Case Case { get; set; }
// ... and several other properties.
}
// in OnModelCreating
modelBuilder.Entity<Appointment>().HasRequired(a => a.Case).WithOptional(c => c.Appointment);
So far, so good: If I create an appointment and (since I have to do so) the referenced case, everything works fine.
But if I create my case and some time later I would like to create an associated appointment, I always get the exception: "Multiplicity constraint violated. The role 'Appointment_Case_Source' of the relationship 'Appointment_Case' has multiplicity 1 or 0..1"
I try to assign appointment to case and vice versa. What is going wrong here?
This is how I try to do this:
private void CreateNewAppointment(Case case)
{
Appointment a = MyRepository<Appointment>.Create();
a.Case = case; // and some other properties...
MyRepository<Appointment>.Update(a);
}
MyRepository is a generic repository class with the following methods:
public T Create()
{
return MyContext.Set<T>().Create(); // with MyContext : DbContext
}
public void Update (T record)
{
if (MyContext.GetEntityState(record) == EntityState.Detached)
{
if (record.Id == 0) { MyContext.Set<T>().Add(record); } // here I get this Multiplicity constraint violation...
// several other things in else
}
}
Kind regards,
Mate
I have a table Device with only one column UID nvarchar(128) and here is my entity:
[Table( Name="Device" )]
public class Device
{
[Key]
public string UID { get; set; }
}
When I trying to insert entity and commit changes to database all is ok. But in database there are no new rows added. If I try to repeat this operation with the same UID - I get en eror
Violation of PRIMARY KEY constraint 'PK_dbo.Devices'. Cannot insert duplicate key in object 'dbo.Devices'. The duplicate key value is ...
What's wrong?
EDIT:
Here is my context:
public class DeviceContext : BaseDbContext, IDbContext
{
public DbSet<Entity.Device> Device { get; set; }
public new IDbSet<T> Set<T>() where T : class
{
return base.Set<T>();
}
public int SaveChanges()
{
return base.SaveChanges();
}
public void Dispose()
{
base.Dispose();
}
}
Fails SaveChanges() method. BaseDbContext is only "connectionstring layer".
DeviceContext context = new DeviceContext();
context.Device.Add(new Device() { UID = id });
context.SaveChanges();
Error says that data is already saved. So I think you are looking at wrong database. Verify connection string which is used by your DbContext.
BTW you can see which connection is used by watching at context.Database.Connection.ConnectionString property in debugger.
EntityFramework's documentation states that the following behavior is possible:
If a foreign key on the dependent entity is nullable, Code First does
not set cascade delete on the relationship, and when the principal is
deleted the foreign key will be set to null.
(from http://msdn.microsoft.com/en-us/jj591620)
However, I cannot achieve such a behavior.
I have the following Entities defined with code-first:
public class TestMaster
{
public int Id { get; set; }
public string Name { get; set; }
public virtual ICollection<TestChild> Children { get; set; }
}
public class TestChild
{
public int Id { get; set; }
public string Name { get; set; }
public virtual TestMaster Master { get; set; }
public int? MasterId { get; set; }
}
Here is the Fluent API mapping configuration:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<TestMaster>()
.HasMany(e => e.Children)
.WithOptional(p => p.Master).WillCascadeOnDelete(false);
modelBuilder.Entity<TestChild>()
.HasOptional(e => e.Master)
.WithMany(e => e.Children)
.HasForeignKey(e => e.MasterId).WillCascadeOnDelete(false);
}
Foreign Key is nullable, navigation property is mapped as Optional, so I expect the cascade delete to work as described as MSDN - i.e. to nullify MasterID's of all children and then delete the Master object.
But when I actually try to delete, I get the FK violation error:
using (var dbContext = new TestContext())
{
var master = dbContext.Set<TestMaster>().Find(1);
dbContext.Set<TestMaster>().Remove(master);
dbContext.SaveChanges();
}
On SaveChanges() it throws the following:
System.Data.Entity.Infrastructure.DbUpdateException : An error occurred while updating the entries. See the inner exception for details.
----> System.Data.UpdateException : An error occurred while updating the entries. See the inner exception for details.
----> System.Data.SqlClient.SqlException : The DELETE statement conflicted with the REFERENCE constraint "FK_dbo.TestChilds_dbo.TestMasters_MasterId". The conflict occurred in database "SCM_Test", table "dbo.TestChilds", column 'MasterId'.
The statement has been terminated.
Am I doing something wrong or did I misunderstood what the MSDN says?
It works indeed as described but the article on MSDN misses to emphasize that it only works if the children are loaded into the context as well, not only the parent entity. So, instead of using Find (which only loads the parent) you must use eager loading with Include (or any other way to load the children into the context):
using (var dbContext = new TestContext())
{
var master = dbContext.Set<TestMaster>().Include(m => m.Children)
.SingleOrDefault(m => m.Id == 1);
dbContext.Set<TestMaster>().Remove(master);
dbContext.SaveChanges();
}
This will delete the master from the database, set all foreign keys in the Child entities to null and write UPDATE statements for the children to the database.
After following #Slauma's great answer I was still getting same error as OP.
So don't be as naive as me and think that the examples below will end up with same result.
dbCtx.Entry(principal).State = EntityState.Deleted;
dbCtx.Dependant.Where(d => d.PrincipalId == principalId).Load();
// code above will give error and code below will work on dbCtx.SaveChanges()
dbCtx.Dependant.Where(d => d.PrincipalId == principalId).Load();
dbCtx.Entry(principal).State = EntityState.Deleted;
First load the children into context before setting entity state to deleted (if you are doing it that way).