<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" schema="Test.dbo" assembly="EmployeeSample" namespace="CSI.Samples.NHibernate">
   <class name="Employee" table="Employee" optimistic-lock="version">
      <id name="EmployeeId" column="EmployeeId" type="Guid">
         <generator class="guid"  />
      </id>
      <version column="Version" type="Int32" name="Version" unsaved-value="0" />
      <bag name="Stores" lazy="true" generic="true" table="StoreEmployee">
         <key column="EmployeeId" />
         <many-to-many class="Store" column="StoreId" />

         <loader query-ref="SelectStoreByEmployeeId" />
         <sql-insert>exec Test.dbo.InsertStoreEmployee ?, ?</sql-insert>
         <sql-delete>exec Test.dbo.DeleteStoreEmployeeByEmployee ?</sql-delete>
      </bag>
      <property column="FirstName" type="String" name="FirstName" />
      <property column="LastName" type="String" name="LastName" />

      <loader query-ref="SelectEmployee"/>
      <sql-insert>exec Test.dbo.InsertEmployee ?, ?, ?, ?, ?, ?, ?</sql-insert>
      <sql-update>exec Test.dbo.UpdateEmployee ?, ?, ?, ?, ?, ?, ?, ?</sql-update>
      <sql-delete>exec Test.dbo.DeleteEmployee ?, ?</sql-delete>
   </class>

  <sql-query name="SelectEmployee">
   <return class="Employee" />
   exec Test.dbo.SelectEmployee @employeeId = :EmployeeId
  </sql-query>
  <sql-query name="SelectEmployeeByStoreId">
    <load-collection alias="employeebystore" role="Store.Employees"/>
    <return class="Employee" />
    exec Test.dbo.SelectEmployeeByStore @storeId = :StoreId
  </sql-query>
  <sql-query name="SelectEmployeeByLastName">
    <return class="Employee" />
    exec Test.dbo.SelectEmployeeByLastName @lastName = :LastName
  </sql-query>
</hibernate-mapping>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" schema="Test.dbo" assembly="EmployeeSample" namespace="CSI.Samples.NHibernate">
   <class name="Store" table="Store" optimistic-lock="version">
      <id name="StoreId" column="StoreId" type="Guid">
         <generator class="guid"  />
      </id>
      <version column="Version" type="Int32" name="Version" unsaved-value="0" />
      <bag name="Employees" inverse="true" lazy="true" generic="true" table="StoreEmployee">
        <key column="StoreId" />
        <many-to-many class="Employee" column="EmployeeId" />
        <loader query-ref="SelectEmployeeByStoreId" />
        <sql-delete>exec Test.dbo.DeleteStoreEmployeeByStore ?</sql-delete>
      </bag>
      <property column="Name" type="String" name="Name" />

      <loader query-ref="SelectStore"/>
      <sql-insert>exec Test.dbo.InsertStore ?, ?, ?, ?, ?</sql-insert>
      <sql-update>exec Test.dbo.UpdateStore ?, ?, ?, ?, ?, ?</sql-update>
      <sql-delete>exec Test.dbo.DeleteStore ?, ?</sql-delete>
   </class>

  <sql-query name="SelectStore">
    <return class="Store" />
    exec Test.dbo.SelectStore @storeId = :StoreId
  </sql-query>
  <sql-query name="SelectStoreByEmployeeId">
    <load-collection alias="storebyemployee" role="Employee.Stores"/>
    <return class="Store" />
    exec Test.dbo.SelectStoreByEmployee @employeeId = :EmployeeId
  </sql-query>
</hibernate-mapping>

Employee employee = session.GetNamedQuery("SelectEmployeeByLastName").SetString("LastName", "Brink").UniqueResult<Employee>();

using (ITransaction transaction = session.BeginTransaction())
{
    employee.Stores.Clear();
    transaction.Commit();
}

NHibernate: exec Test.dbo.SelectEmployeeByLastName @lastName = @p0; @p0 = 'Brink'
NHibernate: exec Test.dbo.UpdateEmployee @p0, @p1, @p2, @p3, @p4; @p0 = '3', @p1 = '5492006b-04bd-4d8f-bb39-b3cd7b9f96cd', @p2 = 'David', @p3 = 'Brink', @p4 = '2'
NHibernate: DELETE FROM Test.dbo.StoreEmployee WHERE EmployeeId = @p0; @p0 = '11f6d2ec-019c-442c-8feb-84b10912d442'

int count = session.Get<Employee>(employee.EmployeeId).Stores.Count;

NHibernate.LazyInitializationException: Failed to lazily initialize a collection ---> NHibernate.ADOException: could not initialize collection: [CSI.Samples.NHibernate.Employee.Stores#7d5afa05-8152-44ed-ac42-63e9bdbd8843] ---> System.NullReferenceException: Object reference not set to an instance of
an object.
   at NHibernate.Loader.DefaultEntityAliases..ctor(IDictionary userProvidedAliases, ILoadable persister, String suffix)
   at NHibernate.Loader.Custom.ColumnEntityAliases..ctor(IDictionary returnProperties, ILoadable persister, String suffix)
   at NHibernate.Loader.Custom.SQLQueryReturnProcessor.GenerateCustomReturns(Boolean queryHadAliases)
   at NHibernate.Loader.Custom.SQLCustomQuery..ctor(ISQLQueryReturn[] queryReturns, String sqlQuery, ICollection additionalQuerySpaces, ISessionFactoryImplementor factory)
   at NHibernate.Impl.SessionImpl.List(NativeSQLQuerySpecification spec, QueryParameters queryParameters, IList results)
   at NHibernate.Impl.SessionImpl.List(NativeSQLQuerySpecification spec, QueryParameters queryParameters)
   at NHibernate.Impl.SqlQueryImpl.List()
   at NHibernate.Persister.Collection.NamedQueryCollectionInitializer.Initialize(Object key, ISessionImplementor session)
   at NHibernate.Persister.Collection.AbstractCollectionPersister.Initialize(Object key, ISessionImplementor session)
   --- End of inner exception stack trace ---
   at NHibernate.Persister.Collection.AbstractCollectionPersister.Initialize(Object key, ISessionImplementor session)
   at NHibernate.Impl.SessionImpl.InitializeCollection(IPersistentCollection collection, Boolean writing)
   at NHibernate.Collection.AbstractPersistentCollection.Initialize(Boolean writing)
   --- End of inner exception stack trace ---
   at NHibernate.Collection.AbstractPersistentCollection.Initialize(Boolean writing)
   at NHibernate.Collection.AbstractPersistentCollection.Read()
   at NHibernate.Collection.Generic.PersistentGenericBag`1.get_Count()