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Hibernate version: 1.2.1.GA

Mapping documents:
Loop.hbm.xml
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
namespace="NhibernateIndexedList"
assembly="NhibernateIndexedList">
<class name="Loop" table="Loop">
<id name="Id" column="Id" type="Int32" access="nosetter.pascalcase-m-underscore" unsaved-value="0">
<generator class="identity" />
</id>
<property name="Name" column="Name" type="string" length="50" not-null="true"/>

<list name="m_DeviceList" access="field" cascade="all">
<key column="LoopId" />
<index column="Position" />
<one-to-many class="Device" />
</list>
</class>
</hibernate-mapping>

Device.hbm.xml
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
namespace="NhibernateIndexedList"
assembly="NhibernateIndexedList">
<class name="Device" table="Device">
<id name="Id" column="Id" type="Int32" access="nosetter.pascalcase-m-underscore" unsaved-value="0">
<generator class="identity" />
</id>
<property name="Name" column="Name" type="string" length="50" not-null="true"/>
</class>
</hibernate-mapping>

Loop.cs:
public class Loop
{
private int m_Id;
private string m_Name;
private IList<Device> m_DeviceList = new List<Device>();

protected Loop()
{
}

public Loop(string name)
{
this.m_Name = name;
}

public virtual int Id
{
get { return this.m_Id; }
}

public virtual string Name
{
get { return this.m_Name; }
set { this.m_Name = value; }
}

public virtual IList<Device> DeviceList
{
get { return this.m_DeviceList; }
}

public virtual void AddDeviceToEnd(Device d)
{
if (d != null && !this.m_DeviceList.Contains(d))
{
this.m_DeviceList.Add(d);
}
}

public virtual void AddDeviceAtPostition(int position, Device d)
{
if (d != null)
{
if (this.m_DeviceList.Contains(d))
{
this.m_DeviceList.Remove(d);
}
if (position >= m_DeviceList.Count)
{
this.m_DeviceList.Add(d);
}
else
{
this.m_DeviceList.Insert(position, d);
}
}
}

public virtual void RemoveDevice(Device d)
{
if (d != null && this.m_DeviceList.Contains(d))
{
this.m_DeviceList.Remove(d);
}
}

public override string ToString()
{
string output;
output = "Loop: " + m_Name + System.Environment.NewLine;

for (int i = 0; i < m_DeviceList.Count; i++)
{
output += i.ToString() + " " + m_DeviceList[i].ToString() + System.Environment.NewLine;
}

return output;
}
}


Code between sessionFactory.openSession() and session.close():

int id;

m_Loop.AddDeviceToEnd(m_FirstDevice);

m_Session.SaveOrUpdate(m_Loop);

Console.WriteLine(m_Loop);

Assert.AreNotEqual(0, m_Loop.Id, "Id should not be zero");
id = m_Loop.Id;

m_Session.Evict(m_Loop);

Loop loop = m_Session.Get<Loop>(id);

Assert.AreEqual(1, loop.DeviceList.Count, "Loop should have 1 device");
Assert.AreEqual("First Device", loop.DeviceList[0].Name, "First Device should be in Position 1");

Full stack trace of any exception that occurs:

Name and version of the database you are using:
SQL Server 2005 Express
The generated SQL (show_sql=true):
NHibernate: INSERT INTO NHList.dbo.Loop (Name) VALUES (@p0); select SCOPE_IDENTITY(); @p0 = 'Loop1'
NHibernate: INSERT INTO NHList.dbo.Device (Name) VALUES (@p0); select SCOPE_IDENTITY(); @p0 = 'First Device'
Loop: Loop1
0 Device: First Device

NHibernate: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=@p0; @p0 = '8'
NHibernate: SELECT m_deviceli0_.LoopId as LoopId__1_, m_deviceli0_.Id as Id1_, m_deviceli0_.Position as Position__1_, m_deviceli0_.Id as Id1_0_, m_deviceli0_.Name as Name1_0_ FROM NHList.dbo.Device m_deviceli0_ WHERE m_deviceli0_.LoopId=@p0; @p0 = '8'

Debug level Hibernate log excerpt:
20:16:38,342 INFO [TestRunnerThread] Environment: PID=960 NHibernate 1.2.1.4000 (1.2.1.4000)
20:16:38,460 INFO [TestRunnerThread] Environment: PID=960 Bytecode provider name : lcg
20:16:38,466 INFO [TestRunnerThread] Environment: PID=960 Using reflection optimizer
20:16:38,540 INFO [TestRunnerThread] Configuration: PID=960 Searching for mapped documents in assembly: NhibernateIndexedList
20:16:38,586 INFO [TestRunnerThread] Configuration: PID=960 Mapping resource: NhibernateIndexedList.Loop.hbm.xml
20:16:39,449 INFO [TestRunnerThread] Dialect: PID=960 Using dialect: NHibernate.Dialect.MsSql2005Dialect
20:16:39,564 INFO [TestRunnerThread] HbmBinder: PID=960 Mapping class: NhibernateIndexedList.Loop -> Loop
20:16:39,611 DEBUG [TestRunnerThread] HbmBinder: PID=960 Mapped property: Id -> Id, type: Int32
20:16:39,636 DEBUG [TestRunnerThread] HbmBinder: PID=960 Mapped property: Name -> Name, type: String
20:16:39,683 DEBUG [TestRunnerThread] HbmBinder: PID=960 Mapped property: m_DeviceList, type: IList`1
20:16:39,688 INFO [TestRunnerThread] Configuration: PID=960 Mapping resource: NhibernateIndexedList.Device.hbm.xml
20:16:39,696 INFO [TestRunnerThread] Dialect: PID=960 Using dialect: NHibernate.Dialect.MsSql2005Dialect
20:16:39,720 INFO [TestRunnerThread] HbmBinder: PID=960 Mapping class: NhibernateIndexedList.Device -> Device
20:16:39,731 DEBUG [TestRunnerThread] HbmBinder: PID=960 Mapped property: Id -> Id, type: Int32
20:16:39,739 DEBUG [TestRunnerThread] HbmBinder: PID=960 Mapped property: Name -> Name, type: String
20:16:39,756 INFO [TestRunnerThread] Configuration: PID=960 checking mappings queue
20:16:39,756 INFO [TestRunnerThread] Configuration: PID=960 processing one-to-many association mappings
20:16:39,787 DEBUG [TestRunnerThread] CollectionSecondPass: PID=960 Second pass for collection: NhibernateIndexedList.Loop.m_DeviceList
20:16:39,805 INFO [TestRunnerThread] HbmBinder: PID=960 mapping collection: NhibernateIndexedList.Loop.m_DeviceList -> Device
20:16:39,822 DEBUG [TestRunnerThread] CollectionSecondPass: PID=960 Mapped collection key: LoopId, index: Position, one-to-many: Device
20:16:39,834 INFO [TestRunnerThread] Configuration: PID=960 processing one-to-one association property references
20:16:39,848 INFO [TestRunnerThread] Configuration: PID=960 processing foreign key constraints
20:16:39,863 DEBUG [TestRunnerThread] Configuration: PID=960 resolving reference to class: Loop
20:16:39,895 INFO [TestRunnerThread] Dialect: PID=960 Using dialect: NHibernate.Dialect.MsSql2005Dialect
20:16:39,913 INFO [TestRunnerThread] ConnectionProviderFactory: PID=960 Initializing connection provider: NHibernate.Connection.DriverConnectionProvider
20:16:39,926 INFO [TestRunnerThread] ConnectionProvider: PID=960 Configuring ConnectionProvider
20:16:39,943 INFO [TestRunnerThread] SettingsFactory: PID=960 Transaction factory: NHibernate.Transaction.AdoNetTransactionFactory
20:16:39,956 INFO [TestRunnerThread] SettingsFactory: PID=960 Optimize cache for minimal puts: False
20:16:39,958 INFO [TestRunnerThread] SettingsFactory: PID=960 Connection release mode: auto
20:16:39,958 INFO [TestRunnerThread] SettingsFactory: PID=960 Default schema set to: NHList.dbo
20:16:39,995 INFO [TestRunnerThread] SettingsFactory: PID=960 echoing all SQL to stdout
20:16:40,013 INFO [TestRunnerThread] SettingsFactory: PID=960 Query translator: NHibernate.Hql.Classic.ClassicQueryTranslatorFactory
20:16:40,025 INFO [TestRunnerThread] SettingsFactory: PID=960 Query language substitutions: {}
20:16:40,040 INFO [TestRunnerThread] SettingsFactory: PID=960 cache provider: NHibernate.Cache.NoCacheProvider, NHibernate, Version=1.2.1.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4
20:16:40,053 INFO [TestRunnerThread] SettingsFactory: PID=960 Using Isolation Level: ReadCommitted
20:16:40,083 INFO [TestRunnerThread] SessionFactoryImpl: PID=960 building session factory
20:16:40,098 DEBUG [TestRunnerThread] SessionFactoryImpl: PID=960 instantiating session factory with properties: {hibernate.connection.provider=NHibernate.Connection.DriverConnectionProvider, hibernate.connection.connection_string=Data Source=localhost\SQLEXPRESS;Initial Catalog=SingletonTest;Integrated Security=True, hibernate.connection.driver_class=NHibernate.Driver.SqlClientDriver, hibernate.show_sql=true, hibernate.use_reflection_optimizer=true, hibernate.default_schema=NHList.dbo, hibernate.connection.isolation=ReadCommitted, hibernate.dialect=NHibernate.Dialect.MsSql2005Dialect}
20:16:40,333 DEBUG [TestRunnerThread] SessionFactoryObjectFactory: PID=960 initializing class SessionFactoryObjectFactory
20:16:40,342 DEBUG [TestRunnerThread] SessionFactoryObjectFactory: PID=960 registered: 566ec28d1df3434e9934f6964e2e3231(unnamed)
20:16:40,354 INFO [TestRunnerThread] SessionFactoryObjectFactory: PID=960 no name configured
20:16:40,447 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Device: SELECT device0_.Id as Id1_0_, device0_.Name as Name1_0_ FROM NHList.dbo.Device device0_ WHERE device0_.Id=?
20:16:40,457 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Device: SELECT device0_.Id as Id1_0_, device0_.Name as Name1_0_ FROM NHList.dbo.Device device0_ WHERE device0_.Id=?
20:16:40,473 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Device: SELECT device0_.Id as Id1_0_, device0_.Name as Name1_0_ FROM NHList.dbo.Device device0_ with (updlock, rowlock) WHERE device0_.Id=?
20:16:40,479 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Device: SELECT device0_.Id as Id1_0_, device0_.Name as Name1_0_ FROM NHList.dbo.Device device0_ with (updlock, rowlock) WHERE device0_.Id=?
20:16:40,501 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Loop: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=?
20:16:40,507 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Loop: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=?
20:16:40,524 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Loop: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ with (updlock, rowlock) WHERE loop0_.Id=?
20:16:40,538 DEBUG [TestRunnerThread] AbstractEntityLoader: PID=960 Static select for entity NhibernateIndexedList.Loop: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ with (updlock, rowlock) WHERE loop0_.Id=?
20:16:40,568 DEBUG [TestRunnerThread] OneToManyLoader: PID=960 Static select for one-to-many NhibernateIndexedList.Loop.m_DeviceList: SELECT m_deviceli0_.LoopId as LoopId__1_, m_deviceli0_.Id as Id1_, m_deviceli0_.Position as Position__1_, m_deviceli0_.Id as Id1_0_, m_deviceli0_.Name as Name1_0_ FROM NHList.dbo.Device m_deviceli0_ WHERE m_deviceli0_.LoopId=?
20:16:40,579 DEBUG [TestRunnerThread] SessionFactoryImpl: PID=960 Instantiated session factory
20:16:40,609 DEBUG [TestRunnerThread] SessionImpl: PID=960 opened session
20:16:40,630 DEBUG [TestRunnerThread] SessionImpl: PID=960 opened session
20:16:40,649 DEBUG [TestRunnerThread] Cascades: PID=960 unsaved-value: 0
20:16:40,660 DEBUG [TestRunnerThread] SessionImpl: PID=960 SaveOrUpdate() unsaved instance
20:16:40,682 DEBUG [TestRunnerThread] SessionImpl: PID=960 saving [NhibernateIndexedList.Loop#<null>]
20:16:40,699 DEBUG [TestRunnerThread] Cascades: PID=960 processing cascades for: NhibernateIndexedList.Loop
20:16:40,707 DEBUG [TestRunnerThread] Cascades: PID=960 done processing cascades for: NhibernateIndexedList.Loop
20:16:40,718 DEBUG [TestRunnerThread] SessionImpl: PID=960 executing insertions
20:16:40,750 DEBUG [TestRunnerThread] WrapVisitor: PID=960 Wrapped collection in role: NhibernateIndexedList.Loop.m_DeviceList
20:16:40,772 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Inserting entity: NhibernateIndexedList.Loop (native id)
20:16:40,826 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened new IDbCommand, open IDbCommands: 1
20:16:40,838 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Building an IDbCommand object for the SqlString: INSERT INTO NHList.dbo.Loop (Name) VALUES (?); select SCOPE_IDENTITY()
20:16:40,857 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Dehydrating entity: [NhibernateIndexedList.Loop#<null>]
20:16:40,869 DEBUG [TestRunnerThread] StringType: PID=960 binding 'Loop1' to parameter: 0
20:16:40,888 DEBUG [TestRunnerThread] SQL: PID=960 INSERT INTO NHList.dbo.Loop (Name) VALUES (@p0); select SCOPE_IDENTITY(); @p0 = 'Loop1'
20:16:40,908 DEBUG [TestRunnerThread] DriverConnectionProvider: PID=960 Obtaining IDbConnection from Driver
20:16:41,287 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened IDataReader, open IDataReaders: 1
20:16:41,318 DEBUG [TestRunnerThread] Int32Type: PID=960 returning '8' as column:
20:16:41,337 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Natively generated identity: 8
20:16:41,338 DEBUG [TestRunnerThread] NHybridDataReader: PID=960 running NHybridDataReader.Dispose()
20:16:41,362 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDataReader, open IDataReaders :0
20:16:41,372 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDbCommand, open IDbCommands: 0
20:16:41,392 DEBUG [TestRunnerThread] ConnectionManager: PID=960 aggressively releasing database connection
20:16:41,401 DEBUG [TestRunnerThread] ConnectionProvider: PID=960 Closing connection
20:16:41,440 DEBUG [TestRunnerThread] Cascades: PID=960 processing cascades for: NhibernateIndexedList.Loop
20:16:41,451 DEBUG [TestRunnerThread] Cascades: PID=960 cascading to collection: NhibernateIndexedList.Loop.m_DeviceList
20:16:41,468 DEBUG [TestRunnerThread] Cascades: PID=960 cascading to SaveOrUpdate()
20:16:41,479 DEBUG [TestRunnerThread] Cascades: PID=960 unsaved-value: 0
20:16:41,493 DEBUG [TestRunnerThread] SessionImpl: PID=960 SaveOrUpdate() unsaved instance
20:16:41,503 DEBUG [TestRunnerThread] SessionImpl: PID=960 saving [NhibernateIndexedList.Device#<null>]
20:16:41,516 DEBUG [TestRunnerThread] SessionImpl: PID=960 executing insertions
20:16:41,530 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Inserting entity: NhibernateIndexedList.Device (native id)
20:16:41,540 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened new IDbCommand, open IDbCommands: 1
20:16:41,553 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Building an IDbCommand object for the SqlString: INSERT INTO NHList.dbo.Device (Name) VALUES (?); select SCOPE_IDENTITY()
20:16:41,567 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Dehydrating entity: [NhibernateIndexedList.Device#<null>]
20:16:41,579 DEBUG [TestRunnerThread] StringType: PID=960 binding 'First Device' to parameter: 0
20:16:41,588 DEBUG [TestRunnerThread] SQL: PID=960 INSERT INTO NHList.dbo.Device (Name) VALUES (@p0); select SCOPE_IDENTITY(); @p0 = 'First Device'
20:16:41,608 DEBUG [TestRunnerThread] DriverConnectionProvider: PID=960 Obtaining IDbConnection from Driver
20:16:41,646 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened IDataReader, open IDataReaders: 1
20:16:41,657 DEBUG [TestRunnerThread] Int32Type: PID=960 returning '5' as column:
20:16:41,669 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Natively generated identity: 5
20:16:41,669 DEBUG [TestRunnerThread] NHybridDataReader: PID=960 running NHybridDataReader.Dispose()
20:16:41,699 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDataReader, open IDataReaders :0
20:16:41,713 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDbCommand, open IDbCommands: 0
20:16:41,728 DEBUG [TestRunnerThread] ConnectionManager: PID=960 aggressively releasing database connection
20:16:41,739 DEBUG [TestRunnerThread] ConnectionProvider: PID=960 Closing connection
20:16:41,756 DEBUG [TestRunnerThread] Cascades: PID=960 done processing cascades for: NhibernateIndexedList.Loop
20:16:41,801 DEBUG [TestRunnerThread] SessionImpl: PID=960 evicting [NhibernateIndexedList.Loop]
20:16:41,810 DEBUG [TestRunnerThread] SessionImpl: PID=960 evicting collection: [<unreferenced>]
20:16:41,825 DEBUG [TestRunnerThread] Cascades: PID=960 processing cascades for: NhibernateIndexedList.Loop
20:16:41,837 DEBUG [TestRunnerThread] Cascades: PID=960 cascading to collection: NhibernateIndexedList.Loop.m_DeviceList
20:16:41,851 DEBUG [TestRunnerThread] Cascades: PID=960 cascading to evict()
20:16:41,866 DEBUG [TestRunnerThread] SessionImpl: PID=960 evicting [NhibernateIndexedList.Device]
20:16:41,875 DEBUG [TestRunnerThread] Cascades: PID=960 done processing cascades for: NhibernateIndexedList.Loop
20:16:41,880 DEBUG [TestRunnerThread] SessionImpl: PID=960 loading [Loop#8]
20:16:41,910 DEBUG [TestRunnerThread] SessionImpl: PID=960 attempting to resolve [Loop#8]
20:16:41,923 DEBUG [TestRunnerThread] SessionImpl: PID=960 object not resolved in any cache [NhibernateIndexedList.Loop#8]
20:16:41,936 DEBUG [TestRunnerThread] AbstractEntityPersister: PID=960 Fetching entity: [NhibernateIndexedList.Loop#8]
20:16:41,957 DEBUG [TestRunnerThread] Loader: PID=960 loading entity: [NhibernateIndexedList.Loop#8]
20:16:41,984 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened new IDbCommand, open IDbCommands: 1
20:16:41,996 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Building an IDbCommand object for the SqlString: SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=?
20:16:42,007 DEBUG [TestRunnerThread] Int32Type: PID=960 binding '8' to parameter: 0
20:16:42,025 INFO [TestRunnerThread] Loader: PID=960 SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=@p0
20:16:42,036 DEBUG [TestRunnerThread] SQL: PID=960 SELECT loop0_.Id as Id0_0_, loop0_.Name as Name0_0_ FROM NHList.dbo.Loop loop0_ WHERE loop0_.Id=@p0; @p0 = '8'
20:16:42,053 DEBUG [TestRunnerThread] DriverConnectionProvider: PID=960 Obtaining IDbConnection from Driver
20:16:42,063 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened IDataReader, open IDataReaders: 1
20:16:42,084 DEBUG [TestRunnerThread] Loader: PID=960 processing result set
20:16:42,101 DEBUG [TestRunnerThread] Loader: PID=960 result set row: 0
20:16:42,115 DEBUG [TestRunnerThread] Loader: PID=960 result row: 8
20:16:42,134 DEBUG [TestRunnerThread] Loader: PID=960 Initializing object from DataReader: [NhibernateIndexedList.Loop#8]
20:16:42,146 DEBUG [TestRunnerThread] Loader: PID=960 Hydrating entity: NhibernateIndexedList.Loop#8
20:16:42,166 DEBUG [TestRunnerThread] StringType: PID=960 returning 'Loop1' as column: Name0_0_
20:16:42,168 DEBUG [TestRunnerThread] Loader: PID=960 done processing result set (1 rows)
20:16:42,191 DEBUG [TestRunnerThread] NHybridDataReader: PID=960 running NHybridDataReader.Dispose()
20:16:42,194 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDataReader, open IDataReaders :0
20:16:42,219 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDbCommand, open IDbCommands: 0
20:16:42,231 DEBUG [TestRunnerThread] ConnectionManager: PID=960 aggressively releasing database connection
20:16:42,244 DEBUG [TestRunnerThread] ConnectionProvider: PID=960 Closing connection
20:16:42,256 DEBUG [TestRunnerThread] Loader: PID=960 total objects hydrated: 1
20:16:42,269 DEBUG [TestRunnerThread] SessionImpl: PID=960 resolving associations for: [NhibernateIndexedList.Loop#8]
20:16:42,284 DEBUG [TestRunnerThread] SessionImpl: PID=960 creating collection wrapper:[NhibernateIndexedList.Loop.m_DeviceList#8]
20:16:42,296 DEBUG [TestRunnerThread] SessionImpl: PID=960 done materializing entity [NhibernateIndexedList.Loop#8]
20:16:42,306 DEBUG [TestRunnerThread] SessionImpl: PID=960 initializing non-lazy collections
20:16:42,314 DEBUG [TestRunnerThread] Loader: PID=960 done entity load
20:16:42,314 DEBUG [TestRunnerThread] ConnectionManager: PID=960 after autocommit
20:16:42,316 DEBUG [TestRunnerThread] ConnectionManager: PID=960 aggressively releasing database connection
20:16:42,357 DEBUG [TestRunnerThread] SessionImpl: PID=960 transaction completion
20:16:42,376 DEBUG [TestRunnerThread] SessionImpl: PID=960 initializing collection [NhibernateIndexedList.Loop.m_DeviceList#8]
20:16:42,386 DEBUG [TestRunnerThread] SessionImpl: PID=960 checking second-level cache
20:16:42,400 DEBUG [TestRunnerThread] SessionImpl: PID=960 collection not cached
20:16:42,418 DEBUG [TestRunnerThread] Loader: PID=960 loading collection: [NhibernateIndexedList.Loop.m_DeviceList#8]
20:16:42,428 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened new IDbCommand, open IDbCommands: 1
20:16:42,430 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Building an IDbCommand object for the SqlString: SELECT m_deviceli0_.LoopId as LoopId__1_, m_deviceli0_.Id as Id1_, m_deviceli0_.Position as Position__1_, m_deviceli0_.Id as Id1_0_, m_deviceli0_.Name as Name1_0_ FROM NHList.dbo.Device m_deviceli0_ WHERE m_deviceli0_.LoopId=?
20:16:42,431 DEBUG [TestRunnerThread] Int32Type: PID=960 binding '8' to parameter: 0
20:16:42,465 INFO [TestRunnerThread] Loader: PID=960 SELECT m_deviceli0_.LoopId as LoopId__1_, m_deviceli0_.Id as Id1_, m_deviceli0_.Position as Position__1_, m_deviceli0_.Id as Id1_0_, m_deviceli0_.Name as Name1_0_ FROM NHList.dbo.Device m_deviceli0_ WHERE m_deviceli0_.LoopId=@p0
20:16:42,478 DEBUG [TestRunnerThread] SQL: PID=960 SELECT m_deviceli0_.LoopId as LoopId__1_, m_deviceli0_.Id as Id1_, m_deviceli0_.Position as Position__1_, m_deviceli0_.Id as Id1_0_, m_deviceli0_.Name as Name1_0_ FROM NHList.dbo.Device m_deviceli0_ WHERE m_deviceli0_.LoopId=@p0; @p0 = '8'
20:16:42,496 DEBUG [TestRunnerThread] DriverConnectionProvider: PID=960 Obtaining IDbConnection from Driver
20:16:42,518 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Opened IDataReader, open IDataReaders: 1
20:16:42,530 DEBUG [TestRunnerThread] Loader: PID=960 result set contains (possibly empty) collection: [NhibernateIndexedList.Loop.m_DeviceList#8]
20:16:42,534 DEBUG [TestRunnerThread] SessionImpl: PID=960 uninitialized collection: initializing
20:16:42,552 DEBUG [TestRunnerThread] Loader: PID=960 processing result set
20:16:42,570 DEBUG [TestRunnerThread] Loader: PID=960 done processing result set (0 rows)
20:16:42,582 DEBUG [TestRunnerThread] NHybridDataReader: PID=960 running NHybridDataReader.Dispose()
20:16:42,598 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDataReader, open IDataReaders :0
20:16:42,612 DEBUG [TestRunnerThread] BatcherImpl: PID=960 Closed IDbCommand, open IDbCommands: 0
20:16:42,624 DEBUG [TestRunnerThread] ConnectionManager: PID=960 aggressively releasing database connection
20:16:42,633 DEBUG [TestRunnerThread] ConnectionProvider: PID=960 Closing connection
20:16:42,634 DEBUG [TestRunnerThread] Loader: PID=960 total objects hydrated: 0
20:16:42,664 DEBUG [TestRunnerThread] SessionImpl: PID=960 1 collections were found in result set
20:16:42,679 DEBUG [TestRunnerThread] SessionImpl: PID=960 collection fully initialized: [NhibernateIndexedList.Loop.m_DeviceList#8]
20:16:42,690 DEBUG [TestRunnerThread] SessionImpl: PID=960 1 collections initialized
20:16:42,701 DEBUG [TestRunnerThread] SessionImpl: PID=960 initializing non-lazy collections
20:16:42,710 DEBUG [TestRunnerThread] Loader: PID=960 done loading collection
20:16:42,729 DEBUG [TestRunnerThread] SessionImpl: PID=960 collection initialized
20:16:42,756 DEBUG [TestRunnerThread] SessionImpl: PID=960 closing session
20:16:42,756 DEBUG [TestRunnerThread] BatcherImpl: PID=960 running BatcherImpl.Dispose(true)
20:16:42,780 DEBUG [TestRunnerThread] AdoTransaction: PID=960 running AdoTransaction.Dispose()

Problems with Session and transaction handling?

Read this: http://hibernate.org/42.html

Have you solved your problem ? For me it looks like the position is not part of the childs mapping, so it will not be saved.