title: HQL with Null check for one-to-one relation
body: <p>I have the following one-to-one relation in Hibernate (that could be null):</p>
  
  <pre><code>&lt;one-to-one name="details" class="com.example.Details" lazy="false" cascade="all"/&gt;
  </code></pre>
  
  <p>I am trying to select all entities that have non-null details with HQL:</p>
  
  <pre><code>from Entity e where e.details is not null
  </code></pre>
  
  <p>but this returns all entities, no matter whether details are null or not. </p>
  
  <p>What would be a correct HQL then?</p>