QueryDsl 단건 조회 샘플

@Test
public void startQueryDsl(){
JPAQueryFactory queryFactory = new JPAQueryFactory(em);
QMember m = new QMember("m");

Member findMember = queryFactory
.select(m)
.from(m)
.where(m.username.eq("member1"))
.fetchOne();
Assertions.assertThat(findMember.getUsername()).isEqualTo("member1");

}

- QMember m = new QMember("m"); - > QMember의 별칭 지정

- QMember qmember = Qmember.member; - > 기본 인스턴스 사용

- .fetchOne() -> 단건 조회 JPQL의 .getSingleResult();와 같은 역할