@OneToMany relationship property not filled

I have implemented Joined, Multiple Table Inheritance.

There is a 'parent' table pois and two sub tables: xPois and yPois and in turn I have an abstract PoiDao class as well as a XPoiDao and a YPoiDao class extending PoiDao.

A poi may have multiple reservations but a reservation belongs to exactly one poi.

Named queries defined in the child table DAOs work well for attributes defined in the respective (direct) table hierarchy. The parent table has a foreign key relationship to another table named reservations (table reservations holds the foreign key of table pois). The problem is that the records from this reservations table get not fetched.

Running this SQL statement in MySql Workbench gets the desired resultset:

SELECT * FROM xPois pp 
    LEFT JOIN pois p ON pp.poiId = p.poiId 
    LEFT JOIN reservations r ON p.poiId = r.poiId 
    WHERE pp.xPoiId = '2011';

In Eclipse I can see {IndirectList: not instantiated} when I inspect the xDao instance in debug mode.

How can I get the records from this table being stored in the PoiDao using JPA?

public abstract class PoiDao implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="poiId")
    private Integer poiId;

    @OneToOne(optional=false, cascade=CascadeType.ALL)
    @JoinColumn(name="addressId",insertable=true,
    updatable=true, unique=true, nullable=false)
    private AddressDao address;

    @Embedded
    private GeoLocationDao geoLocation;

    @Convert("poiTypeConverter")
    private ServiceTypeEnum poiType;
    @Column(name="operator")
    private String operator;

    @Column(name="reservable")
    private boolean reservable;

    @OneToMany(orphanRemoval=true, cascade=CascadeType.ALL, fetch=FetchType.LAZY)
    @JoinColumn(name="poiId", insertable=true, updatable=true)
    private List<ReservationDao>    existingReservations;
    ...
    }

@Entity
@Table(name="xPois")
@DiscriminatorValue("X")
@NamedQueries({
    @NamedQuery(name="XPoiDao.findAll", query="SELECT p FROM XPoiDao p"), 
    @NamedQuery(name="XPoiDao.findByXPoiId", 
                query="SELECT pp FROM XPoiDao pp LEFT JOIN PoiDao p ON pp.poiId = p.poiId "
                        + "LEFT JOIN ReservationDao r ON p.poiId = r.poiId WHERE pp.xPoiId = :xPoiId")
})
@ObjectTypeConverters({
    @ObjectTypeConverter (
            name="xPoiStatusConverter",
            dataType=java.lang.String.class,        // type in DB
            objectType=XPoiStatusEnum.class,    // Java type
            conversionValues={
                @ConversionValue(dataValue="FREE", objectValue="FREE"),
                @ConversionValue(dataValue="OCCUPIED BY VALUE", objectValue="OCCUPIED_BY_VALUE"),
                @ConversionValue(dataValue="OCCUPIED MANUALLY", objectValue="OCCUPIED_MANUALLY"),
                @ConversionValue(dataValue="BLOCKED", objectValue="BLOCKED")
            }
    )
})
public class XPoiDao extends PoiDao implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 2496267921294255723L;

//  @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private Integer             id;

    @Column(name="xPoiId")
    private String              xPoiId;

    @Convert("xPoiStatusConverter")
    @Column(name="status")
    private XPoiStatusEnum status;

    @Embedded
    private ContactDao          contact;

//  @OneToMany(orphanRemoval=true, cascade=CascadeType.ALL, fetch=FetchType.LAZY)
//  @JoinColumn(name="poiId",insertable=true,updatable=true)
//  private List<ReservationDao>    existingReservations;

    @OneToMany(orphanRemoval=true, cascade=CascadeType.ALL, fetch=FetchType.LAZY)
    @JoinColumn(name="parkingPoiId",insertable=true,updatable=true)
    private List<OperatingHourDao> operatingHours;
    ...
    }

You've got FetchType.LAZY in there. Do you get an empty list when you try to access it? Debuggers might not trigger the fetch requests.