6.4. Repository 계층 작성 규칙

6.4.1. Repository 구조

Repository 클래스는 DSLContext를 주입받아 사용합니다.

@Repository
@RequiredArgsConstructor
public class UserRepository {

  private final DSLContext dsl;
}

6.4.2. 조회 (SELECT)

단건 조회:

public Optional<UsersRecord> findById(Long id) {
  return dsl.selectFrom(USERS)
      .where(USERS.ID.eq(id))
      .fetchOptional();
}

public Optional<UsersRecord> findByEmail(String email) {
  return dsl.selectFrom(USERS)
      .where(USERS.EMAIL.eq(email))
      .fetchOptional();
}

목록 조회:

public List<UsersRecord> findAll() {
  return dsl.selectFrom(USERS)
      .orderBy(USERS.CREATED_AT.desc())
      .fetch();
}

public List<UsersRecord> findByIsActive(boolean isActive) {
  return dsl.selectFrom(USERS)
      .where(USERS.IS_ACTIVE.eq(isActive))
      .orderBy(USERS.NAME.asc())
      .fetch();
}

6.4.3. 생성 (INSERT)

public UsersRecord insert(String name, String email) {
  return dsl.insertInto(USERS)
      .set(USERS.NAME, name)
      .set(USERS.EMAIL, email)
      .returning()
      .fetchOne();
}

6.4.4. 수정 (UPDATE)

public int update(Long id, String name) {
  return dsl.update(USERS)
      .set(USERS.NAME, name)
      .set(USERS.UPDATED_AT, OffsetDateTime.now())
      .where(USERS.ID.eq(id))
      .execute();
}

6.4.5. 삭제 (DELETE)

public int deleteById(Long id) {
  return dsl.deleteFrom(USERS)
      .where(USERS.ID.eq(id))
      .execute();
}

6.4.6. 조건 검색 (동적 쿼리)

Condition을 조합하여 동적 쿼리를 작성합니다.

public List<UsersRecord> search(String name, String email, Boolean isActive) {
  Condition condition = DSL.noCondition();

  if (name != null) {
    condition = condition.and(USERS.NAME.containsIgnoreCase(name));
  }
  if (email != null) {
    condition = condition.and(USERS.EMAIL.eq(email));
  }
  if (isActive != null) {
    condition = condition.and(USERS.IS_ACTIVE.eq(isActive));
  }

  return dsl.selectFrom(USERS)
      .where(condition)
      .orderBy(USERS.CREATED_AT.desc())
      .fetch();
}

6.4.7. 조인 쿼리

public List<Record> findOrdersWithUserName(Long userId) {
  return dsl.select(
          ORDERS.ID,
          ORDERS.PRODUCT_NAME,
          ORDERS.AMOUNT,
          USERS.NAME.as("user_name"))
      .from(ORDERS)
      .join(USERS).on(ORDERS.USER_ID.eq(USERS.ID))
      .where(ORDERS.USER_ID.eq(userId))
      .orderBy(ORDERS.CREATED_AT.desc())
      .fetch();
}

6.4.8. 페이지네이션

public List<UsersRecord> findPage(int page, int size) {
  return dsl.selectFrom(USERS)
      .orderBy(USERS.CREATED_AT.desc())
      .limit(size)
      .offset(page * size)
      .fetch();
}

public long count() {
  return dsl.fetchCount(USERS);
}

서비스 레이어에서 페이지 응답을 조립합니다:

public PageResponse<UserResponse> findUsers(int page, int size) {
  List<UsersRecord> records = userRepository.findPage(page, size);
  long totalElements = userRepository.count();

  List<UserResponse> content = records.stream()
      .map(UserResponse::from)
      .toList();

  return new PageResponse<>(content, page, size, totalElements);
}