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결과 쿼리 개수가 맞지 않아서 문의 드립니다.

23.10.25 22:05 작성 23.10.25 22:18 수정 조회수 389

0

[질문 템플릿]
1. 강의 내용과 관련된 질문인가요? 예
2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? 예
3. 질문 잘하기 메뉴얼을 읽어보셨나요? 예

[질문 내용]

[간단한 주문 조회 V3: 엔티티를 DTO로 변환 -패치 조인 최적화] 강의에서 5분 50초 쯤에 v2를 돌려봤을 때, 강사님은 쿼리가 5번 나오는데,

저는 계속 7번이 나오더라구요...

order가 처음에 주문 2개를 만들어서 이미 영속성 상태라 그 다음에는 1차 캐시에서 가져오는 것으로 보여 쿼리는 생성이 안되어야 한다고 생각이 드는데, 왜 계속 order 쿼리가 2번 더 나오는 걸까요...?

 

[Query]

2023-10-25T21:54:33.448+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

o1_0.order_id,

o1_0.deliver_id,

o1_0.member_id,

o1_0.order_date,

o1_0.status

from

orders o1_0

join

member m1_0

on m1_0.member_id=o1_0.member_id

fetch

first ? rows only

2023-10-25T21:54:33.449+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473449 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 join member m1_0 on m1_0.member_id=o1_0.member_id fetch first ? rows only

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 join member m1_0 on m1_0.member_id=o1_0.member_id fetch first 1000 rows only;

2023-10-25T21:54:33.450+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

m1_0.member_id,

m1_0.city,

m1_0.street,

m1_0.zipcode,

m1_0.name

from

member m1_0

where

m1_0.member_id=?

2023-10-25T21:54:33.451+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473451 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select m1_0.member_id,m1_0.city,m1_0.street,m1_0.zipcode,m1_0.name from member m1_0 where m1_0.member_id=?

select m1_0.member_id,m1_0.city,m1_0.street,m1_0.zipcode,m1_0.name from member m1_0 where m1_0.member_id=1;

2023-10-25T21:54:33.451+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

d1_0.delivery_id,

d1_0.city,

d1_0.street,

d1_0.zipcode,

d1_0.status

from

delivery d1_0

where

d1_0.delivery_id=?

2023-10-25T21:54:33.451+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473451 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select d1_0.delivery_id,d1_0.city,d1_0.street,d1_0.zipcode,d1_0.status from delivery d1_0 where d1_0.delivery_id=?

select d1_0.delivery_id,d1_0.city,d1_0.street,d1_0.zipcode,d1_0.status from delivery d1_0 where d1_0.delivery_id=1;

2023-10-25T21:54:33.452+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

o1_0.order_id,

o1_0.deliver_id,

o1_0.member_id,

o1_0.order_date,

o1_0.status

from

orders o1_0

where

o1_0.deliver_id=?

2023-10-25T21:54:33.452+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473452 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 where o1_0.deliver_id=?

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 where o1_0.deliver_id=1;

2023-10-25T21:54:33.453+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

m1_0.member_id,

m1_0.city,

m1_0.street,

m1_0.zipcode,

m1_0.name

from

member m1_0

where

m1_0.member_id=?

2023-10-25T21:54:33.453+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473453 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select m1_0.member_id,m1_0.city,m1_0.street,m1_0.zipcode,m1_0.name from member m1_0 where m1_0.member_id=?

select m1_0.member_id,m1_0.city,m1_0.street,m1_0.zipcode,m1_0.name from member m1_0 where m1_0.member_id=2;

2023-10-25T21:54:33.453+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

d1_0.delivery_id,

d1_0.city,

d1_0.street,

d1_0.zipcode,

d1_0.status

from

delivery d1_0

where

d1_0.delivery_id=?

2023-10-25T21:54:33.454+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473454 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select d1_0.delivery_id,d1_0.city,d1_0.street,d1_0.zipcode,d1_0.status from delivery d1_0 where d1_0.delivery_id=?

select d1_0.delivery_id,d1_0.city,d1_0.street,d1_0.zipcode,d1_0.status from delivery d1_0 where d1_0.delivery_id=2;

2023-10-25T21:54:33.454+09:00 DEBUG 37176 --- [nio-8080-exec-3] org.hibernate.SQL :

select

o1_0.order_id,

o1_0.deliver_id,

o1_0.member_id,

o1_0.order_date,

o1_0.status

from

orders o1_0

where

o1_0.deliver_id=?

2023-10-25T21:54:33.454+09:00 INFO 37176 --- [nio-8080-exec-3] p6spy : #1698238473454 | took 0ms | statement | connection 11| url jdbc:h2:tcp://localhost/~/jpashop2

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 where o1_0.deliver_id=?

select o1_0.order_id,o1_0.deliver_id,o1_0.member_id,o1_0.order_date,o1_0.status from orders o1_0 where o1_0.deliver_id=2;

 

 

 

 

[OrderSimpleApiController]

package jpabook.jpashop2.api;

import jpabook.jpashop2.Repository.OrderRepository;
import jpabook.jpashop2.Repository.OrderSearch;
import jpabook.jpashop2.domain.Address;
import jpabook.jpashop2.domain.Order;
import jpabook.jpashop2.domain.OrderStatus;
import lombok.Data;
import lombok.RequiredArgsConstructor;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.time.LocalDateTime;
import java.util.List;
import java.util.stream.Collectors;

/**
* X To One (컬렉션 X)
* Order
* Order -> Member
* Order -> Delivery
*/
@RestController
@RequiredArgsConstructor
public class OrderSimpleApiController {

private final OrderRepository orderRepository;

@GetMapping("/api/v1/simple-orders")
public List<Order> ordersV1(){
List<Order> all = orderRepository.findAllByString(new OrderSearch());
for (Order order : all) {
order.getMember().getName(); // Lazy 강제 초기화
order.getDelivery().getAddress(); // Lazy 강제 초기화
}
return all;
}

@GetMapping("/api/v2/simple-orders")
public List<SimpleOrderDto> ordersV2(){
// Order 2개
List<Order> orders = orderRepository.findAllByString(new OrderSearch());

List<SimpleOrderDto> result = orders.stream()
.map(o -> new SimpleOrderDto(o)) // map : a -> b로 치환
.collect(Collectors.toList());
return result;
}

@GetMapping("/api/v3/simple-orders")
public List<SimpleOrderDto> ordersV3() {

List<Order> orders = orderRepository.findAllWithMemberDelivery();
List<SimpleOrderDto> result = orders.stream()
.map(o -> new SimpleOrderDto(o))
.collect(Collectors.toList());

return result;
}


@Data
static class SimpleOrderDto{ // API 명세서
private Long orderId;
private String name;
private LocalDateTime orderDate;
private OrderStatus orderStatus;
private Address address;

public SimpleOrderDto(Order order) {
orderId = order.getId();
name = order.getMember().getName();
orderDate = order.getOrderDate();
orderStatus = order.getStatus();
address = order.getDelivery().getAddress();
}
}
}

 

 

[OrderRepository]

...

 

public List<Order> findAllWithMemberDelivery() {
return em.createQuery("select o from Order o" +
" join fetch o.member m" +
" join fetch o.delivery d", Order.class)
.getResultList();
}

 

course-thumbnail

실전! 스프링 부트와 JPA 활용2 - API 개발과 성능 최적화

간단한 주문 조회 V3: 엔티티를 DTO로 변환 - 페치 조인 최적화

강의실 바로가기

답변 2

·

답변을 작성해보세요.

0

김영한님의 프로필

김영한

지식공유자

2023.10.27

안녕하세요. rr8602님

다음을 참고해주세요 :)

https://www.inflearn.com/questions/1040920

감사합니다.

0

codesweaver님의 프로필

codesweaver

2023.10.26

안녕하세요. rr8602님, 공식 서포터즈 코즈위버 입니다.

도움을 드리고 싶지만 질문 내용만으로는 답변을 드리기 어렵습니다.

실제 동작하는 전체 프로젝트를 압축해서 구글 드라이브로 공유해서 링크를 남겨주세요.

구글 드라이브 업로드 방법은 다음을 참고해주세요.

https://bit.ly/3fX6ygx


주의: 업로드시 링크에 있는 권한 문제 꼭 확인해주세요


추가로 다음 내용도 코멘트 부탁드립니다.

1. 문제 영역을 실행할 수 있는 방법

2. 문제가 어떻게 나타나는지에 대한 상세한 설명

감사합니다.

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