일 | 월 | 화 | 수 | 목 | 금 | 토 |
---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | |||
5 | 6 | 7 | 8 | 9 | 10 | 11 |
12 | 13 | 14 | 15 | 16 | 17 | 18 |
19 | 20 | 21 | 22 | 23 | 24 | 25 |
26 | 27 | 28 | 29 | 30 | 31 |
- 자바
- JDBC
- Android
- SpringBoot
- kotlin
- 스프링
- Greedy
- java
- 김영한
- Exception
- 알고리즘
- 그리디
- Thymeleaf
- JPQL
- db
- springdatajpa
- QueryDSL
- Servlet
- 스프링 핵심 원리
- Proxy
- 백준
- Spring Boot
- transaction
- 스프링 핵심 기능
- http
- AOP
- spring
- pointcut
- jpa
- 인프런
- Today
- Total
목록jpa (149)
개발자되기 프로젝트
1. 순수 JPA기반 Repository @Repository public class TeamRepository { @PersistenceContext private EntityManager em; public Team save(Team team){ em.persist(team); return team; } public void delete(Team team){ em.remove(team); } public List findAll(){ return em.createQuery("select t from Team t", Team.class).getResultList(); } public Optional findById(Long id){ Team findTeam = em.find(Team.class, id);..
1. Entity Class Member와 Team은 다대일 연관관계 2. ERD 3. Member class xToOne은 기본적으로 fetch type이 EAGER이다. 항상 LAZY를 적용하자(지연로딩) package study.datajpa.entity; import lombok.*; import javax.persistence.*; @Entity @Getter @Setter @NoArgsConstructor(access = AccessLevel.PROTECTED) @ToString(of = {"id", "userName", "age"}) public class Member { @Id @GeneratedValue @Column(name = "member_id") private Long id; pr..
1. application.yml spring: datasource: url: jdbc:h2:tcp://localhost/~/datajpa username: sa driver-class-name: org.h2.Driver jpa: hibernate: ddl-auto: create properties: hibernate: format_sql: true logging.level: org.hibernate.SQL: debug 2. 엔티티를 만들자. @Entity @Getter @Setter public class Member { @Id @GeneratedValue private Long id; private String userName; protected Member() { } public Member(Str..
Open Session In View : Hibernate Open EntityManager In View : JPA (관례적으로.. osiv라 함.) 1. OSIV on spring.jpa.open-in-view : true기본값 따라서 spring 실행하면 아래와 같은 주의를 볼 수 있음. 2021-08-25 22:21:56.054 WARN 18844 --- [ restartedMain] JpaBaseConfiguration$JpaWebConfiguration : spring.jpa.open-in-view is enabled by default. Therefore, database queries may be performed during view rendering. Explicitly configur..
다 조인시켜서 한방쿼리로 가져오자. 1. OrderFlatDto Order와 OrderItem을 join해서 DTO로 한번에 가져올 예정. DB에서 join하면 한줄로 쭉 join 되듯이 데이터 구조를 맞춤. @Data public class OrderFlatDto { //order private Long orderId; private String name; private LocalDateTime orderDate; private OrderStatus orderStatus; private Address address; //orderItem private String itemName; private int orderPrice; private int count; public OrderFlatDto(Long ..
1. 최적화 public List findAllByDto_optimization() { List result = findOrders(); List orderIds = toOrderIds(result); Map orderItemMap = findOrderItemMap(orderIds); //메모리에 map을 올려놓고 찾아서 꽂아넣기. result.forEach(o -> o.setOrderItems(orderItemMap.get(o.getOrderId()))); return result; } private List toOrderIds(List result) { List orderIds = result.stream().map(o -> o.getOrderId()) .collect(Collectors.toList..
1. DTO를 직접 가져오기 위해 DTO 및 repository생성. @Data public class OrderQueryDto { private Long orderId; private String name; private LocalDateTime orderDate; private OrderStatus orderStatus; private Address address; private List orderItems; public OrderQueryDto(Long orderId, String name, LocalDateTime orderDate, OrderStatus orderStatus, Address address) { this.orderId = orderId; this.name = name; this.o..
1. fetch join fetch join을 적용해서 일대다 조회를 해보자. public List findAllWithItem(){ List resultList = em.createQuery("select o from Order o " + "join fetch o.member m " + "join fetch o.delivery d " + "join fetch o.orderItems oi " + "join fetch oi.item i", Order.class).getResultList(); return resultList; } 현재 db에 order는 2개, orderItem은 4개 가 있다. 일대다 관계이기 때문에 DB입장에서 ORDER,와 ORDER_ITEM을 JOIN하면 ORDER의 DATA가 불어..