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.as("memberId"),
                    member.username,
                    member.age,
                    team.id.as("teamId"),
                    team.name.as("teamName")))
            .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 hasText(username) ? member.username.eq(username) : null ;
}

private BooleanExpression teamNameEq(String teamName) {
    return hasText(teamName) ? team.name.eq(teamName) : null ;
}

private BooleanExpression ageGoe(Integer ageGoe) {
    return ageGoe != null ? member.age.eq(ageGoe) : null;
}

private BooleanExpression ageLoe(Integer ageLoe) {
    return ageLoe != null ? member.age.eq(ageLoe) : null;
}

참고: where 절에 파라미터 방식을 사용하면 조건 재사용 가능

 

//where 파라미터 방식은 이런식으로 재사용이 가능하다.
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();
}

 

 

 

 

 

출처 : 김영한 JPA 스프링 데이터 강의