<hibernate-mapping>
  <class name="eg.Thing">
        <id name="thingId" type="java.lang.Long">
            <column name="id"/>
            <generator class="assigned" />
        </id>
        <property name="name" type="string">
          <column name="name"/>
        </property>
        <property name="createDate" type="date">
          <column name="cre_d"/>
        </property>
        <many-to-one name="thingHolder" class="eg.ThingHolder">
          <column name="thing_holder_id"/>
        </many-to-one>
  </class>
</hibernate-mapping>

<hibernate-mapping>
  <class name="eg.ThingHolder">
        <id name="thingHolderId" type="java.lang.Long">
            <column name="thing_holder_id"/>
            <generator class="assigned" />
        </id>
        <property name="name" type="string">
          <column name="name"/>
        </property>
        <property name="createDate" type="date">
          <column name="cre_d"/>
        </property>
        <set name="things" inverse="true">
          <key>
            <column name="id"/>
          </key>
          <one-to-many class="eg.Thing"/>
        </set>
  </class>
</hibernate-mapping>

public class Thing {
  private Long thingId;
  private String name;
  private Date createDate;
  private eg.ThingHolder thingHolder;

  // Getters and setters omitted for clarity
}

public class ThingHolder {
  private Long thingHolderId;
  private String name;
  private Set things = new HashSet();

  // Getters and setters omitted for clarity
  // With bidirection associations, some collection management routines are highly suggested
  // for example:
  public void addThing(Thing thing) {
    this.getThings.add(thing);
    thing.setThingHolder(this);
    // null-safety and exception checking omitted for clarity
  }
}

  // Things from thing_holder_id
  session.createQuery("from Things as thing where thing.holder.id=?");
  // There are many other ways of accomplishing this same query, this example uses implicit joining

  // ThingHolder from id
  session.createQuery("from ThingHolder as holder where holder.things.id=?");
  // I'd never do it this way, preferring to load the Thing instance and navigating to the ThingHolder via the getThingHolder() method

PK          NAME
--          ----
0           Name0
1           Name1
2           Name2
3           Name3
4           Name4