Backgound: i use JPA (hibernate impl) + spring I have two tables, the first one is ok, it has one primary key and it works even with java.Util.Date fields. Another one has 3 parameters in primary key(it is first time i work with it):
PRIMARY KEY (`id_room`,`id_hotel`,`day`),
Full schema:
CREATE TABLE `hotels` (
  `id_room` int(11) NOT NULL DEFAULT '0',
  `id_hotel` int(11) NOT NULL DEFAULT '0',
  `day` date NOT NULL,
  PRIMARY KEY (`id_room`,`id_hotel`,`day`),
  KEY `id_hotel` (`id_hotel`,`day`),
  KEY `day` (`day`),
  KEY `day-hotel` (`day`,`id_hotel`),
  KEY `hotel` (`id_hotel`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
So i added code to my Entity:
@Entity @IdClass(HotelId.class)
@Table(name="hotels")
public class Hotels implements Serializable {
    private static final Long serialVersionUID = 1L;
    @Id
    @Column(name="id_room")
    private int roomId;
    @Id
    @Column(name="id_hotel")
    private int hotelId;
    @Id
    @Temporal(TemporalType.DATE)
    private Date day;
....
HotelId.class
public class HotelId implements Serializable {
    private int roomId;
    private int hotelId;
    private Date day;
    public HotelId() {
    }
    public HotelId(int roomId, int hotelId, Date day) {
        this.roomId = roomId;
        this.hotelId = hotelId;
        this.day = day;
    }
    public int getRoomId() {
        return roomId;
    }
    public int getHotelId() {
        return hotelId;
    }
    public Date getDay() {
        return day;
    }
}
With this entity i stuck for a long time:
I spent almost all day today for this problem. I have database with date column in format(yyyy-mm-dd). I also have entity class in project with java.util.Date date field. Now i'm trying to make a select:
TypedQuery query = em.createQuery("Select h FROM Hotels h where h.roomId=:roomId and h.hotelId=:hotelId and h.day=:day", Hotels.class);
query.setParameter("roomId", roomId);
query.setParameter("hotelId", hotelId);
query.setParameter("day", date);
It says there is no data
Now i change date field from java.util.Date to String and change my query:
TypedQuery query = em.createQuery("Select h FROM Hotels h where h.roomId=:roomId and h.hotelId=:hotelId and h.day=:day", Hotels.class);
query.setParameter("roomId", roomId);
query.setParameter("hotelId", hotelId);
query.setParameter("day", new SimpleDateFormat("yyyy-mm-dd").format(date));
It finds data.
The question is how to send date(java.util.Date) to MySql DB and get back an information?
Update:
It doesnt work also
@Entity 
    @Table(name="hotels")
    public class Hotels implements Serializable {
        private static final Long serialVersionUID = 1L;
        @Id
        private int id;
        @Column(name="id_room")
        private int roomId;
        @Column(name="id_hotel")
        private int hotelId;
        private java.sql.Date day;
        ....
    }
Query:
    java.sql.Date sqlDate = new java.sql.Date(day.getTime());
    TypedQuery query = em.createQuery("Select h FROM Hotels h where h.roomId=:roomId and h.hotelId=:hotelId and h.day=:day", Hotels.class);
query.setParameter("roomId", roomId);
query.setParameter("hotelId", hotelId);
            query.setParameter("day", sqlDate);
 
     
    