Querydsl - 동적 쿼리와 성능 최적화 조회 Where절 파라미터 사용

동적 쿼리와 성능 최적화 조회 - Where절 파라미터 사용

Where절에 파라미터를 사용한 예제

public List<MemberTeamDto> search(MemberSearchCondition condition) {
    return queryFactory
            .select(new QMemberTeamDto(
                    member.id,
                    member.username,
                    member.age,
                    team.id,
                    team.name
            ))
            .from(member)
            .leftJoin(member.team, team)
            .where(
                    usernameEq(condition.getUsername()),
                    teamNameEq(condition.getTeamName()),
                    ageGoe(condition.getAgeGoe()),
                    ageLoe(condition.getAgeLoe()))
            .fetch();
}
private BooleanExpression usernameEq(String username) {
    return isEmpty(username) ? null : member.username.eq(username);
}
private BooleanExpression teamNameEq(String teamName) {
    return isEmpty(teamName) ? null : member.team.name.eq(teamName);
}
private BooleanExpression ageGoe(Integer ageGoe) {
    return ageGoe == null ? null : member.age.goe(ageGoe);
}
private BooleanExpression ageLoe(Integer ageLoe) {
    return ageLoe == null ? null : member.age.loe(ageLoe);
}

참고 : where 절에 파라미터 방식을 사용하면 조건 재사용 가능

public List<Member> findMember(MemberSearchCondition condition) {
      return queryFactory
            .selectFrom(member)
            .leftJoin(member.team, team)
            .where(usernameEq(condition.getUsername()),
                    teamNameEq(condition.getTeamName()),
                    ageGoe(condition.getAgeGoe()),
                    ageLoe(condition.getAgeLoe()))
            .fetch();
 }

테스트

@Test
void search() {
    Team teamA = new Team("teamA");
    Team teamB = new Team("teamB");

    em.persist(teamA);
    em.persist(teamB);

    Member member1 = new Member("member1", 10, teamA);
    Member member2 = new Member("member2", 20, teamA);
    Member member3 = new Member("member3", 30, teamB);
    Member member4 = new Member("member4", 40, teamB);

    em.persist(member1);
    em.persist(member2);
    em.persist(member3);
    em.persist(member4);

    MemberSearchCondition condition = new MemberSearchCondition();

    condition.setAgeGoe(35);
    condition.setAgeLoe(40);
    condition.setTeamName("teamB");

    List<MemberTeamDto> result = memberJapRepository.search(condition);

    assertThat(result).extracting("username").containsExactly("member4");
}

인프런 김영한 지식공유자님 강의 : 실전! Querydsl