Question

My class has a nullable guid property which is not it’s identifier. The guid is used to group records in a specific way, so that many records can have the same guid.
Everytime I update some other property, nhibernate updates the guid, which is not the desired result.

Here’s the mapping:

<class name="MyClass" table="SomeTable">
    <id name="Id" column="SomeTableId" type="Int32" >
      <generator class="native">
        <param name="sequence">SomeTableSequence</param>
      </generator>
    </id>
    <property name="Instant" column="Instant" />
    <property name="Value" column="Value" />
    <property name="Description" column="Description" />  
    <property name="Group" column="GroupId" /> <!-- this is the GUID -->
  </class>

What should I do to stop this behavior?

Update

I forgot to mention that I’m simply doing an ISession.Update call:

public void Update(MyClass myInstance) {
    _session.Update(myInstance);
    _session.Flush();
}

Answer 1

Since I didn’t have much time available, I ended up doing the update “by hand”. I’ll gladly accept another answer, if any.