DTO 바로 받기 $사용 (ORM으로 해결 안 될 경우) - 2

[ 쿼리문 ]

select id, title, content, user_id, (select count(id) from reply_tb where board_id = bt.id) reply_count from board_tb bt;

[ 뽑고자 하는 데이터 ]

[ BoardResponse ] - Count용 DTO 생성

@AllArgsConstructor
@Data
public class CountDTO {
    private Integer id;
    private String title;
    private String content;
    private Integer userId;
    private Long replyCount;
}

[ BoardJPARepository ] - BoardQueryRepository로 해도 될 듯

@Query("select new shop.mtcoding.blog.board.BoardResponse$CountDTO(b.id, b.title, b.content, b.user.id, (select count(r.id) from Reply r where r.board.id = b.id)) from Board b")
List<BoardResponse.CountDTO> findAllWithReplyCount();

[ 테스트 ]

@Test
public void findAllWithReplyCount_test(){
    // given

    // when
    List<BoardResponse.CountDTO> boardCountDTOList = boardJPARepository.findAllWithReplyCount();
    System.out.println(boardCountDTOList);
    // then
}