nhibernate 3.0 optimistic lock and related entities - nhibernate

Question

I've noticed in my database (SQL Server) that the column I'm using for versioning is getting updated for an entity whenever that entity is added to a related table.
So, for example, if I have a Person entity and I add a Person to a Club, the Person's record in the database will have a new version. Of course, in the database, it's the Club's record that is added/updated with the Person's primary key.
I'm a bit surprised by that behavior because no other data for the Person entity is changing.
My question is if there is a way to turn that off; that is, to only have the version column updated when data in that row changes. What might the implications of that kind of configuration be?
EDIT Here's the real code
Model
public partial class ObligationProgramFund : IMyObject
{
private System.Int32 _id;
// ... many other properties
private IList<ObligationProgramFundOrganization> _obligationPFOrganizations;
private System.Byte[] _recordVersion;
public ObligationProgramFund() : base()
{
_obligationPFOrganizations = new List<ObligationProgramFundOrganization>();
}
public virtual System.Int32 Id
{
get { return _id; }
set { _id = value; }
}
public virtual IList<ObligationProgramFundOrganization> ObligationPFOrganizations
{
get { return _obligationPFOrganizations; }
set { _obligationPFOrganizations = value; }
}
public virtual System.Byte[] RecordVersion
{
get { return _recordVersion; }
set { _recordVersion = value; }
}
}
public partial class ObligationProgramFundOrganization : IMyObject
{
private ObligationProgramFund _obligationProgramFund;
private System.Int32 _id;
private Organization _organization;
private System.Byte[] _recordVersion;
// .. other properties
public ObligationProgramFundOrganization() : base()
{
}
public virtual System.Int32 Id
{
get { return _id; }
set { _id = value; }
}
public virtual System.Byte[] RecordVersion
{
get { return _recordVersion; }
set { _recordVersion = value; }
}
public virtual ObligationProgramFund ObligationProgramFund
{
get { return _obligationProgramFund; }
set { _obligationProgramFund = value; }
}
public virtual Organization Organization
{
get { return _organization; }
set { _organization = value; }
}
}
public partial class Organization : IMyObject
{
private IList<ObligationProgramFundOrganization> _obligationPFOrganizations;
private System.Int32 _id;
private System.Byte[] _recordVersion;
// other properties
public Organization() : base()
{
_obligationPFOrganizations = new List<ObligationProgramFundOrganization>();
}
public virtual System.Int32 Id
{
get { return _id; }
set { _id = value; }
}
public virtual System.Byte[] RecordVersion
{
get { return _recordVersion; }
set { _recordVersion = value; }
}
public virtual IList<ObligationProgramFundOrganization> ObligationPFOrganizations
{
get { return _obligationPFOrganizations; }
set { _obligationPFOrganizations = value; }
}
}
Mapping
public partial class ObligationProgramFundMap : ClassMap<ObligationProgramFund>
{
public ObligationProgramFundMap()
{
Table("[MySchema2].[dbo].[ObligationProgramFund]");
OptimisticLock.Version();
DynamicUpdate();
LazyLoad();
Id(x=>x.Id)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[Id]")
.GeneratedBy.Identity();
Version(x=>x.RecordVersion)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[RecordVersion]")
.CustomSqlType("timestamp")
.Not.Nullable()
.UnsavedValue("null")
.CustomType("BinaryBlob")
.Generated.Always();
// other properties/components
HasMany(x=>x.ObligationPFOrganizations)
.Access.CamelCaseField(Prefix.Underscore)
.Cascade.AllDeleteOrphan()
.Fetch.Select()
.Inverse()
.LazyLoad()
.KeyColumns.Add("ObligationProgramFundId");
}
}
public partial class ObligationProgramFundOrganizationMap : ClassMap<ObligationProgramFundOrganization>
{
public ObligationProgramFundOrganizationMap()
{
Table("[MySchema2].[dbo].[ObligationProgramFundOrganization]");
OptimisticLock.Version();
DynamicUpdate();
LazyLoad();
Id(x=>x.Id)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[Id]")
.GeneratedBy.Identity();
Version(x=>x.RecordVersion)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[RecordVersion]")
.CustomSqlType("timestamp")
.Not.Nullable()
.UnsavedValue("null")
.CustomType("BinaryBlob")
.Generated.Always();
// other properties
References(x=>x.ObligationProgramFund)
.Access.CamelCaseField(Prefix.Underscore)
.Cascade.SaveUpdate()
.Fetch.Select()
.Columns("ObligationProgramFundId");
References(x=>x.Organization)
.Access.CamelCaseField(Prefix.Underscore)
.Cascade.SaveUpdate()
.Fetch.Select()
.Columns("OrganizationId");
}
}
public partial class OrganizationMap : ClassMap<Organization>
{
public OrganizationMap()
{
Table("[MySchema2].[dbo].[Organization]");
OptimisticLock.Version();
DynamicUpdate();
LazyLoad();
Id(x=>x.Id)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[Id]")
.GeneratedBy.Identity();
Version(x=>x.RecordVersion)
.Access.CamelCaseField(Prefix.Underscore)
.Column("[RecordVersion]")
.CustomSqlType("timestamp")
.Not.Nullable()
.UnsavedValue("null")
.CustomType("BinaryBlob")
.Generated.Always();
// other properties
HasMany(x=>x.ObligationPFOrganizations)
.Access.CamelCaseField(Prefix.Underscore)
.Cascade.AllDeleteOrphan()
.Fetch.Select()
.Inverse()
.LazyLoad()
.KeyColumns.Add("OrganizationId");
}
}
So my entities are
Organization 1 - ∞ ObligationProgramFundOrganization ∞ - 1 ObligationProgramFund
The issue I've observed is when a new ObligationProgramFundOrganization is created (the associative table), the record version for ObligationProgramFund is updated.
The actual senario is that I have a table of ObligationProgramFundOrganizations on the ObligationProgramFund edit form. A ObligationProgramFundOrganization is added via AJAX calls. When I go to then save the ObligationProgramFund, I get a concurrency exception. I am sure no other user actually edited the ObligationProgramFund as it's all running locally.

Answer 1

(I've posted an answer to a similar question: Why NHibernate UPDATE reference entity?)
You have version column specified. Which means that any property change (even collection) trigger version update.
In order to prevent a certain property/collection to change version, optimistic-lock="false" property should be set in xml mapping.