querydsl : search, resultFetch, sort, paging, aggregation, group

querydsl/src/main/resources/application.yml

@@ -11,6 +11,7 @@ spring:
     properties:
       hibernate:
         format_sql: true
+        use_sql_comments: true
 
 logging.level:
   org.hibernate.SQL: debug

querydsl/src/test/java/com/example/querydsl/QuerydslBasicTest.java

@@ -2,7 +2,10 @@ package com.example.querydsl;
 
 import com.example.querydsl.entity.Member;
 import com.example.querydsl.entity.QMember;
+import com.example.querydsl.entity.QTeam;
 import com.example.querydsl.entity.Team;
+import com.querydsl.core.QueryResults;
+import com.querydsl.core.Tuple;
 import com.querydsl.jpa.impl.JPAQueryFactory;
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
@@ -13,6 +16,10 @@ import org.springframework.transaction.annotation.Transactional;
 
 import javax.persistence.EntityManager;
 
+import java.util.List;
+
+import static com.example.querydsl.entity.QMember.*;
+import static com.example.querydsl.entity.QTeam.*;
 import static org.assertj.core.api.Assertions.*;
 
 @SpringBootTest
@@ -56,14 +63,144 @@ public class QuerydslBasicTest {
 
     @Test
     void startQuerydsl() {
-        QMember m = new QMember("m");
-
         Member findMember = queryFactory
-                .select(m)
-                .from(m)
-                .where(m.username.eq("member1")) // 파라미터 바인딩 처리
+                .select(member)
+                .from(member)
+                .where(member.username.eq("member1")) // 파라미터 바인딩 처리
                 .fetchOne();
 
         assertThat(findMember.getUsername()).isEqualTo("member1");
     }
+
+    @Test
+    void search() {
+        Member findMember = queryFactory
+                .selectFrom(member)
+                .where(member.username.eq("member1")
+                        .and(member.age.eq(10)))
+                .fetchOne();
+
+        assertThat(findMember.getUsername()).isEqualTo("member1");
+    }
+
+    @Test
+    void searchAndParam() {
+        Member findMember = queryFactory
+                .selectFrom(member)
+                .where(
+                        member.username.eq("member1"),
+                        member.age.eq(10)
+                )
+                .fetchOne();
+
+        assertThat(findMember.getUsername()).isEqualTo("member1");
+    }
+
+    @Test
+    void resultFetch() {
+        List<Member> fetch = queryFactory
+                .selectFrom(member)
+                .fetch();
+        Member fetchOne = queryFactory
+                .selectFrom(member)
+                .where(member.username.eq("member1"))
+                .fetchOne();
+        Member fetchFirst = queryFactory
+                .selectFrom(member)
+                .fetchFirst();
+        QueryResults<Member> fetchResults = queryFactory
+                .selectFrom(member)
+                .fetchResults();
+        long total = fetchResults.getTotal();
+        List<Member> content = fetchResults.getResults();
+
+        long fetchCount = queryFactory
+                .selectFrom(member)
+                .fetchCount();
+    }
+
+    /**
+     * 회원 정렬 순서
+     * 1. 회원 나이 내림차순
+     * 2. 회원 이름 올림차순
+     * 단 2에서 회원 이름이 없으면 마지막에 출력(nulls last)
+    */
+    @Test
+    void sort() {
+        em.persist(new Member(null, 100));
+        em.persist(new Member("member5", 100));
+        em.persist(new Member("member6", 100));
+
+        List<Member> result = queryFactory
+                .selectFrom(member)
+                .where(member.age.eq(100))
+                .orderBy(member.age.desc(), member.username.asc().nullsLast())
+                .fetch();
+
+        Member member5 = result.get(0);
+        Member member6 = result.get(1);
+        Member memberNull = result.get(2);
+        assertThat(member5.getUsername()).isEqualTo("member5");
+        assertThat(member6.getUsername()).isEqualTo("member6");
+        assertThat(memberNull.getUsername()).isNull();
+    }
+
+    @Test
+    void paging1() {
+        QueryResults<Member> result = queryFactory
+                .selectFrom(member)
+                .orderBy(member.username.desc())
+                .offset(1)
+                .limit(2)
+                .fetchResults();
+
+        assertThat(result.getTotal()).isEqualTo(4);
+        assertThat(result.getLimit()).isEqualTo(2);
+        assertThat(result.getOffset()).isEqualTo(1);
+        assertThat(result.getResults().size()).isEqualTo(2);
+    }
+
+    @Test
+    void aggregation() {
+        List<Tuple> result = queryFactory
+                .select(
+                        member.count(),
+                        member.age.sum(),
+                        member.age.avg(),
+                        member.age.max(),
+                        member.age.min()
+                )
+                .from(member)
+                .fetch();
+
+        Tuple tuple = result.get(0);
+
+        assertThat(tuple.get(member.count())).isEqualTo(4);
+        assertThat(tuple.get(member.age.sum())).isEqualTo(100);
+        assertThat(tuple.get(member.age.avg())).isEqualTo(25);
+        assertThat(tuple.get(member.age.max())).isEqualTo(40);
+        assertThat(tuple.get(member.age.min())).isEqualTo(10);
+    }
+
+    /**
+     * 팀의 이름과 각 팀의 평균 연령 구하기
+     */
+    @Test
+    void group() throws Exception {
+        List<Tuple> result = queryFactory
+                .select(team.name, member.age.avg())
+                .from(member)
+                .join(member.team, team)
+                .groupBy(team.name)
+                .fetch();
+
+        Tuple teamA = result.get(0);
+        Tuple teamB = result.get(1);
+
+        assertThat(teamA.get(team.name)).isEqualTo("teamA");
+        assertThat(teamA.get( member.age.avg())).isEqualTo(15);
+
+        assertThat(teamB.get(team.name)).isEqualTo("teamB");
+        assertThat(teamB.get( member.age.avg())).isEqualTo(35);
+    }
 }