How to pull an alias from native query in JPA - spring

Question

I'm trying to pull an alias from native query in JPA, something like (SUM,COUNT), Well the method can return an integer if i pulled SUM or COUNT perfectly (ONLY if i pulled it alone) .
but how can i pull it with the rest of object? here is a sample what i am trying to do
#Entity
#Table("hotels")
public class Hotel {
#Column(name="id")
#Id
private int hotelId;
#Column(name="hotel_name")
private String hotelName;
#OneToMany
private List<Availability>list;
private int avaialbeCount; //this one should be Aliased and need to be pulled by none column
}
Repository
public interface HotelRepository extends JpaRepository<Hotel,Integer>{
#Query(value="select h.*,a.count(1) as avaialbeCount from hotels h INNER JOIN availability a on (a.hotel_id=h.hotel_id) group by a.date",nativeQuery=true)
public List<Hotel> getHotels();
}
in the above repository. im trying to get avaialbeCount with hotel columns but im unable to pull it, however i can pull it by removing the select h.* and keep select COUNT only and make the method returns Integer instead of Hotel

Answer 1

You can use JPQL, something like this
#Query("SELECT new test.Hotel(h.hotelName, count(h)) FROM Hotel h GROUP BY h.hotelName")
to use this new test.Hotel(h.hotelName, count(h)) construction, you need constructor like
public Hotel(String hotelName, Long avaialbeCount) {
this.hotelName = hotelName;
this.avaialbeCount = avaialbeCount;
}
Example:
Repository:
package test;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.stereotype.Repository;
import java.util.List;
#Repository
public interface HotelRepo extends JpaRepository<Hotel, Long> {
#Query("SELECT new test.Hotel(h.hotelName, count(h)) FROM Hotel h GROUP BY h.hotelName")
List<Hotel> getHotelsGroupByName();
}
Entity:
package test;
import javax.persistence.*;
#Entity
#Table(name = "hotels")
public class Hotel {
#Id
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long hotelId;
#Column(name = "hotel_name")
private String hotelName;
#Transient
private Long avaialbeCount;
public Hotel() {
}
public Hotel(String hotelName) {
this.hotelName = hotelName;
}
public Hotel(String hotelName, Long avaialbeCount) {
this.hotelName = hotelName;
this.avaialbeCount = avaialbeCount;
}
#Override
public String toString() {
return "Hotel{" +
"hotelId=" + hotelId +
", hotelName='" + hotelName + '\'' +
", avaialbeCount=" + avaialbeCount +
'}';
}
}
#Transient annotation is used to indicate that a field is not to be persisted in the database.