NHibernate forces UPDATE-statement when I access child

Question

Hi,

I have a parent to child relationship.

My problem is, when I access the child object, and afterward flushes the session, NHibernate automatically UPDATE's the child objects with the same values (no differences).

This will issue an update of the child:

Response.Write(Profile.ProfilePicture.Filename);
_session.Flush();

Can anyone see why this happens? I of course don't want to update the child in this scenario.

Here is my hibernate mapping:

Parent:

<class name="Business.Domain.Profile, Business" table="Profiles">  
    <id name="Id" type="int">
      <generator class="native" />
    </id>
    <property name="Username" type="string" length="100" />
    <property name="Password" type="string" length="200" />
    <property name="Email" type="string" length="150" />
    <property name="CreatedDate" generated="insert" />
    <property name="LastLoginDate" />
    <property name="LastActivityDate" />
    <property name="Firstname" type="string" length="50" />
    <property name="Lastname" type="string" length="50" />
    <property name="Fullname" formula="Firstname + ' ' + Lastname" />
    <property name="Gender" not-null="true" type="int" />
    <property name="Description" not-null="false" type="string" />

    <many-to-one
      name="ProfilePicture" 
      column="ProfilePictureId" 
      class="Business.Domain.Picture, Business" />

    <set name="Pictures" generic="true" inverse="true" cascade="all-delete-orphan">
      <key column="ProfileId" />
      <one-to-many class="Business.Domain.Picture, Business"/>
    </set>
  </class>

Child:

  <class name="Business.Domain.Picture, Avando.Business" table="Pictures">
    <id name="Id" type="int">
      <generator class="native" />
    </id>
    <property name="Filename" type="string" />
    <property name="CreatedDate" type="DateTime" generated="insert" />

    <many-to-one
      name="Profile"
      column="ProfileId"
      class="Business.Domain.Profile, Business"
      not-null="true" />    
  </class>

Answer 1

I sorted this out my self.

The update happend because of the property:

Is actually an enum :)