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Fluent NHibernate: One to One Mapping - reverse from primary column to a foreign key

I have a "Group" class and a "GroupSummaryLevel" class, codes are given below. There is a one-to-one relation between these entities in DB. I need the "GroupSummaryLevel" as a property in Groups class. It is supposed to be a very simple join like
(SELECT g.Id FROM GroupSummaryLevel g WHERE g.AcctGroup = GroupID)
Unfortunately, I wasn't able to figure this out how to do with NHibernate. The many answers I saw here is no help to me. I would appreaciate any inputs from the more experienced NHibernate users out there. Thanks in advance.
public class Group : DomainEntity
{
public virtual string GroupId { get; set; }
public virtual string GroupName { get; set; }
public virtual GroupSummaryLevel GroupSummaryLevel { get; set; }
}
public class GroupSummaryLevel : DomainEntity
{
public virtual int Id { get; set; }
public virtual string AcctGroup { get; set; }
public virtual GroupSummaryLevel Parent { get; set; }
public virtual IList<GroupSummaryLevel> Children { get; set; }
public GroupSummaryLevel()
{
Children = new List<GroupSummaryLevel>();
}
}
The mapping I have done did not work so far. My mapping codes are as below:
public GroupMap()
{
Table("Groups");
LazyLoad();
Id(x => x.GroupId).GeneratedBy.Assigned().Column("GroupID").CustomType<TrimmedString>();
Map(x => x.GroupName).Column("GroupName").CustomType<TrimmedString>().Not.Nullable();
HasOne(x => x.GroupSummaryLevel).Cascade.None().ForeignKey("AcctGroup");
}
public GroupSummaryLevelMap()
{
Table("GroupSummaryLevel");
LazyLoad();
Id(x => x.Id).GeneratedBy.Identity().Column("Id");
Map(x => x.AcctGroup).Column("AcctGroup").CustomType<TrimmedString>().Not.Nullable();
//References(x => x.Parent).Column("ParentId");
//HasMany(x => x.Children).Cascade.All().KeyColumn("ParentId");
}
Note: I also need to do a self-join for GroupSummaryLevel, and no success with that either. Any recommendations for that will also be appreciated :)

I would say, that your one-to-one is not driven by primary/foreign keys, but by property-ref. So the Group should map the summary by saying something like this:
...if you want to find related SummaryLevel, pass my <id> into column mapped as AcctGroup
public GroupMap()
{
...
HasOne(x => x.GroupSummaryLevel)
.Cascade.None()
//.ForeignKey("AcctGroup")
.PropertyRef(gsl => gsl.AcctGroup)
;
}
public GroupSummaryLevelMap()
{
...
//References(x => x.Parent).Column("ParentId");
//HasMany(x => x.Children).Cascade.All().KeyColumn("ParentId");
References(x => x.Parent, "AcctGroup");
}
NOTEs for completeness, as discussed in comments:
In this scenario, when the "child" has reference to parent - it really calls for one-to-many/.HasMany() mapping.
The down side is, that child is represented as a colleciton of children: IList<GroupSummaryLevel>. It is not as straighforward to use, but we can create some virtual property, returning the .FirstOrDefault(). The benefit we get - is lazy loading (not in place with one-to-one).

NHibernate Envers: Cannot insert duplicate key in object

I'm using Envers to audit tables, but it's creating some audit tables for unknown/absent tables.
It's looks like a Many To Many relation audit table for Many To One relations.
Is this right? If it's, Why?
dbo.HorarioFixo - OK
dbo.HorarioFixo_Auditoria - OK
dbo.HorarioFixo_JanelaHorarioFixo_Auditoria - NOK
dbo.JanelaHorarioFixo - OK
dbo.JanelaHorarioFixo_Auditoria - OK
But when I try to remove/delete and HorarioFixo I'm getting an error.
The error I'm getting:
NHibernate.Exceptions.GenericADOException
could not execute batch command.[SQL: SQL not available]
em NHibernate.Engine.ActionQueue.BeforeTransactionCompletionProcessQueue.BeforeTransactionCompletion()
em NHibernate.Impl.SessionImpl.BeforeTransactionCompletion(ITransaction tx)
em NHibernate.Transaction.AdoTransaction.Commit()
em Foo.Testes.Servicos.TesteCanalDeTransmissaoService.RemoveDependenciasCorretamente() na TesteCanalDeTransmissaoService.cs: line 195
System.Data.SqlClient.SqlException
Violation of PRIMARY KEY constraint 'PK__HorarioF__450088476960C81E'. Cannot insert duplicate key in object 'dbo.HorarioFixo_JanelaHorarioFixo_Auditoria'.
Violation of PRIMARY KEY constraint 'PK__HorarioF__450088476960C81E'. Cannot insert duplicate key in object 'dbo.HorarioFixo_JanelaHorarioFixo_Auditoria'.
The statement has been terminated.
The statement has been terminated.
This is the SQL duplicated:
exec sp_executesql N'INSERT INTO HorarioFixo_JanelaHorarioFixo_Auditoria (REVTYPE, REV, HorarioFixoId, JanelaHorarioFixoId) VALUES (#p0, #p1, #p2, #p3)',N'#p0 tinyint,#p1 int,#p2 bigint,#p3 bigint',#p0=2,#p1=3,#p2=1,#p3=2 go
All this is a part of the code. If you need something more, leave a comment.
My classes:
public class Entidade
{
protected Entidade();
public virtual long Id { get; set; }
public virtual long Version { get; set; }
public abstract override bool Equals(object obj);
public override int GetHashCode();
}
public class Horario : Entidade
{
protected Horario()
{
}
}
public class HorarioFixo : Horario
{
public virtual int Frequencia { get; set; }
public virtual ICollection<JanelaHorarioFixo> JanelasRemessa { get; set; }
public virtual ICollection<JanelaHorarioFixo> JanelasRetorno { get; set; }
}
public class JanelaHorarioFixo : Entidade
{
public virtual TimeSpan HorarioInicio { get; set; }
public virtual TimeSpan? HorarioLimite { get; set; }
}
My mappings:
public class HorarioMap : ClassMapping<Horario>
{
public HorarioMap()
{
Id(x => x.Id, mapper =>
{
mapper.Generator(Generators.Identity);
mapper.UnsavedValue(0);
});
}
}
public class HorarioFixoMap : JoinedSubclassMapping<HorarioFixo>
{
public HorarioFixoMap()
{
Property(x => x.Frequencia);
Bag(x => x.JanelasRemessa, m =>
{
m.Cascade(Cascade.All);
m.Lazy(CollectionLazy.NoLazy);
}, map => map.OneToMany());
Bag(x => x.JanelasRetorno, m =>
{
m.Cascade(Cascade.All);
m.Lazy(CollectionLazy.NoLazy);
}, map => map.OneToMany());
}
}
public class JanelaHorarioFixoMap : ClassMapping<JanelaHorarioFixo>
{
public JanelaHorarioFixoMap()
{
Id(x => x.Id, mapper =>
{
mapper.Generator(Generators.Identity);
mapper.UnsavedValue(0);
});
Property(x => x.HorarioInicio, m => m.NotNullable(true));
Property(x => x.HorarioLimite, m => m.NotNullable(false));
}
}
NH and Envers configurations:
var ormHelper = ORMHelperUtils.GetORMHelper();
var mapper = new MyConventionModelMapper();
_config = new Configuration();
mapper.AddMappings(ormHelper.GetMappings());
mapper.AddMapping(typeof(REVINFOMap));
ormHelper.SetupApplicationNeeds(_config);
_config.AddMapping(mapper.CompileMappingForAllExplicitlyAddedEntities());
_config.SetProperty(Environment.CurrentSessionContextClass, "call");
if (ormHelper.UseEnvers)
{
var classesDominio = ormHelper.GetDomainTables();
if (classesDominio.Any())
{
var envers = new FluentConfiguration();
envers.Audit(classesDominio);
envers.SetRevisionEntity<REVINFO>(e => e.Id, e => e.Date, new CustomRevisionListener());
_config.SetEnversProperty(ConfigurationKey.AuditTableSuffix, "_Auditoria");
_config.IntegrateWithEnvers(envers);
}
}

I've just changed my class to
public class HorarioFixo : Horario
{
public virtual int Frequencia { get; set; }
public virtual ICollection<JanelaHorarioFixo> Janelas { get; set; }
}
And added a property to JanelaHorarioFixo to identify the type. But the table dbo.HorarioFixo_JanelaHorarioFixo_Auditoria is still there, and I don't know why.

If you use unidirectional one-to-many, Envers needs a link table to be able to have correct history.
If you use bidirectional one-to-many, no link table is needed.
See this answer.

Fluent NHibernate ManyToOne Reference Property Name issue

I was using Fluent NHibernate and I had these two entities:
public class Location
{
public virtual int Id { get; protected set; }
public virtual string Name { get; set; }
private Stack<Place> _places;
public virtual IList<Place> Places
{
get { return _places.ToList(); }
set { _places = new Stack<Place>(value); }
}
public virtual void AddPlace(Place place)
{
_places.Push(place);
place.LocationReference = this;
}
}
public class Place
{
public virtual int Id { get; protected set; }
public virtual Location LocationReference { get; set; }
}
mapped as follow:
class LocationMap : ClassMap<Location>
{
public LocationMap()
{
Id(x => x.Id);
Map(x => x.Name)
.Not.Nullable()
.Unique();
HasMany(x => x.Places)
.Cascade.All()
.Inverse();
}
}
class PlaceMap : ClassMap<Place>
{
public PlaceMap()
{
Id(x => x.Id);
References(x => x.LocationReference);
}
}
I was using SQLite as RDBMS and I was saving only the Location, relying on Cascade() for managing Places insertion.
The two entities were successfully inserted in the DB, but when I tried to read a Location back and to access its list of Places, the list was empty.
After removing Inverse(), the code seemed to properly work. But when I inspected the DB, I found two columns within the Place table, while I expected only one of them: Location_id (that was empty) and LocationReference_id (that was set).
After one whole day of desperate googling, I noticed that everyone was naming the reference property as the class itself. So, I renamed it from LocationReference to Location, I added back the Inverse() call and everything worked fine. Only the column Location_id was in the DB, of course.
Does anyone know why this happened? Thanks.

NHibernate References Dont' save Foreign Key

I have 2 classes that reference each other. It's a weird situation that our CRM needs.
I have an Organization and EmAddress tables and classes. The Organization inherits from Subscriber, which also has a table. I think this could be my problem, or the fact that I can't set Inverse on these because there is no "HasMany"...
The order of insert/update is ..
INSERT Email
INSERT Org
UPDATE Email to set Email.Subscriber
Email.Subscriber needs to be "NOT NULL", so this doesn't work. How can I change the order, I can't use Inverse because there is no list. Just 2 references.
public class Organization : Subscriber
{
public override string Class { get { return "Organization"; } }
EmAddress PrimaryEmailAddress {get;set;}
}
public class OrganizationMap : SubclassMap<Organization>
{
public OrganizationMap()
{
Table("Organization");
KeyColumn("Organization");
References(x => x.PrimaryEmail,"PrimaryEmailAddress").Cascade.SaveUpdate();
}
}
public EmAddressMap()
{
Id(x => x.Id, "EmAddress");
Map(x => x.EmailAddress, "eMailAddress");
References<Subscriber>(x => x.Subscriber,"Subscriber").LazyLoad().Fetch.Select().Not.Nullable();
/*not.nullable() throw s error. NHibernate INSERTS email, INSERTS org, UPDATES email. */
}
public class EmAddress
{
public virtual Guid Id { get; set; }
public virtual string EmailAddress { get; set; }
public virtual Subscriber Subscriber { get; set; }
}
//Implementation
var session = NHIbernateHelper.GetSession();
using(var tx = session.BeginTransaction())
{
var org = new Organization();
org.PrimaryEmail = new EmAddress(){Subscriber = org};
session.Save(org);
tx.commit();
}

This post might help:
http://ayende.com/blog/3960/nhibernate-mapping-one-to-one
Have only one side use many-to-one (Fluent: "References") and the other side uses one-to-one (Fluent: "HasOne").

Fluent nhibernate one to one mapping

How do I make a one to one mapping.
public class Setting
{
public virtual Guid StudentId { get; set; }
public virtual DateFilters TaskFilterOption { get; set; }
public virtual string TimeZoneId { get; set; }
public virtual string TimeZoneName { get; set; }
public virtual DateTime EndOfTerm { get; set; }
public virtual Student Student { get; set; }
}
Setting Class map:
public SettingMap()
{
// Id(Reveal.Member<Setting>("StudentId")).GeneratedBy.Foreign("StudentId");
//Id(x => x.StudentId);
Map(x => x.TaskFilterOption)
.Default(DateFilters.All.ToString())
.NvarcharWithMaxSize()
.Not.Nullable();
Map(x => x.TimeZoneId)
.NvarcharWithMaxSize()
.Not.Nullable();
Map(x => x.TimeZoneName)
.NvarcharWithMaxSize()
.Not.Nullable();
Map(x => x.EndOfTerm)
.Default("5/21/2011")
.Not.Nullable();
HasOne(x => x.Student);
}
Student Class map
public class StudentMap: ClassMap<Student>
{
public StudentMap()
{
Id(x => x.StudentId);
HasOne(x => x.Setting)
.Cascade.All();
}
}
public class Student
{
public virtual Guid StudentId { get; private set; }
public virtual Setting Setting { get; set; }
}
Now every time I try to create a settings object and save it to the database it crashes.
Setting setting = new Setting
{
TimeZoneId = viewModel.SelectedTimeZone,
TimeZoneName = info.DisplayName,
EndOfTerm = DateTime.UtcNow.AddDays(-1),
Student = student
};
The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Settings_Students". The conflict occurred in database "Database", table "dbo.Students", column 'StudentId'.
The statement has been terminated.
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: The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Settings_Students". The conflict occurred in database "Database", table "dbo.Students", column 'StudentId'.
The statement has been terminated.
What am I missing?
Edit
public class StudentMap: ClassMap<Student>
{
public StudentMap()
{
Id(x => x.StudentId)
.GeneratedBy.Guid();
HasOne(x => x.Setting)
.PropertyRef("Student")
.Cascade.All();
}
}
public class SettingMap: ClassMap<Setting>
{
public SettingMap()
{
Id(x => x.StudentId)
.GeneratedBy.Guid();
Map(x => x.TaskFilterOption)
.Default(DateFilters.All.ToString())
.NvarcharWithMaxSize().Not.Nullable();
Map(x => x.TimeZoneId)
.NvarcharWithMaxSize().Not.Nullable();
Map(x => x.TimeZoneName)
.NvarcharWithMaxSize().Not.Nullable();
Map(x => x.EndOfTerm)
.Default("5/21/2011").Not.Nullable();
References(x => x.Student).Unique();
}
}
Setting setting = new Setting
{
TimeZoneId = viewModel.SelectedTimeZone,
TimeZoneName = info.DisplayName,
EndOfTerm = DateTime.UtcNow.AddDays(-1),
Student = student
};
studentRepo.SaveSettings(setting);
studentRepo.Commit();
I get these error for both ways
Invalid index 5 for this SqlParameterCollection with Count=5. 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.IndexOutOfRangeException: Invalid index 5 for this SqlParameterCollection with Count=5. Source Error: Line 76: using (ITransaction transaction = session.BeginTransaction()) Line 77: { Line 78: transaction.Commit(); Line 79: } Line 80: }

There are two basic ways how to map bidirectional one-to-one association in NH. Let's say the classes look like this:
public class Setting
{
public virtual Guid Id { get; set; }
public virtual Student Student { get; set; }
}
public class Student
{
public virtual Guid Id { get; set; }
public virtual Setting Setting { get; set; }
}
Setting class is a master in the association ("aggregate root"). It is quite unusual but it depends on problem domain...
Primary key association
public SettingMap()
{
Id(x => x.Id).GeneratedBy.Guid();
HasOne(x => x.Student).Cascade.All();
}
public StudentMap()
{
Id(x => x.Id).GeneratedBy.Foreign("Setting");
HasOne(x => x.Setting).Constrained();
}
and a new setting instance should be stored:
var setting = new Setting();
setting.Student = new Student();
setting.Student.Name = "student1";
setting.Student.Setting = setting;
setting.Name = "setting1";
session.Save(setting);
Foreign key association
public SettingMap()
{
Id(x => x.Id).GeneratedBy.Guid();
References(x => x.Student).Unique().Cascade.All();
}
public StudentMap()
{
Id(x => x.Id).GeneratedBy.Guid();
HasOne(x => x.Setting).Cascade.All().PropertyRef("Student");
}
Primary key association is close to your solution. Primary key association should be used only when you are absolutely sure that the association will be always one-to-one. Note that AllDeleteOrphan cascade is not supported for one-to-one in NH.
EDIT: For more details see:
http://fabiomaulo.blogspot.com/2010/03/conform-mapping-one-to-one.html
http://ayende.com/blog/3960/nhibernate-mapping-one-to-one

Here a complete sample with foreign key association
using System;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using NHibernate;
using FluentNHibernate.Mapping;
namespace NhOneToOne
{
public class Program
{
static void Main(string[] args)
{
try
{
var sessionFactory = Fluently.Configure()
.Database(
MsSqlConfiguration.MsSql2005
.ConnectionString(#"Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=NHTest;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=True;ApplicationIntent=ReadWrite;MultiSubnetFailover=False")
.ShowSql()
)
.Mappings(m => m
.FluentMappings.AddFromAssemblyOf<Program>())
.BuildSessionFactory();
ISession session = sessionFactory.OpenSession();
Parent parent = new Parent();
parent.Name = "test";
Child child = new Child();
child.Parent = parent;
parent.Child = child;
session.Save(parent);
session.Save(child);
int id = parent.Id;
session.Clear();
parent = session.Get<Parent>(id);
child = parent.Child;
}
catch (Exception e)
{
Console.Write(e.Message);
}
}
}
public class Child
{
public virtual string Name { get; set; }
public virtual int Id { get; set; }
public virtual Parent Parent { get; set; }
}
public class Parent
{
public virtual string Name { get; set; }
public virtual int Id { get; set; }
public virtual Child Child { get; set; }
}
public class ChildMap : ClassMap<Child>
{
public ChildMap()
{
Table("ChildTable");
Id(x => x.Id).GeneratedBy.Native();
Map(x => x.Name);
References(x => x.Parent).Column("IdParent");
}
}
public class ParentMap : ClassMap<Parent>
{
public ParentMap()
{
Table("ParentTable");
Id(x => x.Id).GeneratedBy.Native();
Map(x => x.Name);
HasOne(x => x.Child).PropertyRef(nameof(Child.Parent));
}
}
}
And the SQL to create tables
CREATE TABLE [dbo].[ParentTable] (
[Id] INT IDENTITY (1, 1) NOT NULL,
[Name] VARCHAR (MAX) NULL
);
CREATE TABLE [dbo].[ChildTable] (
[Id] INT IDENTITY (1, 1) NOT NULL,
[IdParent] INT NOT NULL,
[Name] VARCHAR (50) NULL
);
ALTER TABLE [dbo].[ChildTable]
ADD CONSTRAINT [FK_ChildTable_ToTable] FOREIGN KEY ([IdParent]) REFERENCES [dbo].[ParentTable] ([Id]);

First, define one of the sides of the relationship as Inverse(), otherwise there is a redundant column in the database and this may cause the problem.
If this doesn't work, output the SQL statements generated by NHibernate (using ShowSql or through log4net) and try to understand why the foreign key constraint is violated (or post it here with the SQL, and don't forget the values of the bind variables that appear afer the SQL statement).

You should not define the StudentId in Sesstings class. Sessting class already has it (from
public virtual Student Student { get; set; } ). Probably it should be SesstingId and you should map the Id field as well (you have to define/map the primary key).