동적쿼리 : BooleanBuilder, Where 다중 파라미터

1. 동적쿼리 두 가지 방법

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• BooleanBuilder
• Where 다중 파라미터 사용

 

 

2. BooleanBuilder

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• booleanBuilder에 and, or 조건 추가 가능.

    private List<Member> searchMember1(String usernameCon, Integer ageCon) {

        BooleanBuilder builder = new BooleanBuilder();
        if(usernameCon != null){
            builder.and(member.username.eq(usernameCon)); //booleanbuild에 and조건 추가
        }

        if(ageCon!=null){
            builder.and(member.age.eq(ageCon));
        }

        return queryFactory
                .selectFrom(member)
                .where(builder)
                .fetch();
    }

    select
        member1 
    from
        Member member1 
    where
        member1.username = ?1 
        and member1.age = ?2

 

 

3. Where 다중 파라미터 사용 : 히힛

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• ㅠwhere의 조건들은 and로 묶임
• where 조건에 null 값은 무시된다.
• 메서드를 다른 쿼리에서도 재활용 할 수 있다.
• 쿼리 자체의 가독성이 높아진다.

    @Test
    public void dynamicQuery_WhereParam(){
        String usernameParam = "member1";
        Integer ageParam = 10;

        List<Member> result =  searchMember2(usernameParam, ageParam);
        assertThat(result.size()).isEqualTo(1);
    }

    private List<Member> searchMember2(String usernameCon, Integer ageCon) {

        return queryFactory
                .selectFrom(member)
                .where(usernameEq(usernameCon), ageEq(ageCon)) //where에 null들어가면 무시. 여러 조건이 들어가면 and로 처리됨.
                .fetch();
    }

    private BooleanExpression usernameEq(String usernameCon) {
        return usernameCon == null ? null : member.username.eq(usernameCon);
    }

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

select
        member1 
    from
        Member member1 
    where
        member1.username = ?1 
        and member1.age = ?2

• 심지서 각 where 조건은 메서드로 뽑았기 때문에 조립도 가능.

    @Test
    public void dynamicQuery_WhereParam(){
        String usernameParam = "member1";
        Integer ageParam = 10;

        List<Member> result =  searchMember2(usernameParam, ageParam);
        assertThat(result.size()).isEqualTo(1);
    }

    private List<Member> searchMember2(String usernameCon, Integer ageCon) {

        return queryFactory
                .selectFrom(member)
                //.where(usernameEq(usernameCon), ageEq(ageCon)) //where에 null들어가면 무시. 여러 조건이 들어가면 and로 처리됨.
                .where(allEq(usernameCon, ageCon))
                .fetch();
    }

    private BooleanExpression usernameEq(String usernameCon) {
        return usernameCon == null ? null : member.username.eq(usernameCon);
    }

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

    private BooleanExpression allEq(String usernameCon, Integer ageCon){
        return usernameEq(usernameCon).and(ageEq(ageCon));
    }

 

4. GitHub : 210903 Dynamic Query

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GitHub - bsh6463/Querydsl