[BE] 상품에 대한 리뷰 목록 조회 N+1 문제 완전히 해결

[70825]

어떤 기능을 구현하나요?

#607 에서 완전히 해결하지 못했던 N+1 문제를 해결했습니다.

위 사진에서 Review를 통해 ReviewTag까지는 가져올 수 있었지만, Tag는 못가져왔던 문제를 해결했어요
그래서 쿼리 14개가 날아가던걸 3개로 줄였습니다

• 최종적으로 개선된 쿼리 수 : 92개 → 14개 → 3개

쿼리문

Hibernate: 
    select
        product0_.id as id1_4_0_,
        product0_.average_rating as average_2_4_0_,
        product0_.category_id as category8_4_0_,
        product0_.content as content3_4_0_,
        product0_.image as image4_4_0_,
        product0_.name as name5_4_0_,
        product0_.price as price6_4_0_,
        product0_.review_count as review_c7_4_0_ 
    from
        product product0_ 
    where
        product0_.id=?
Hibernate: 
    select
        review0_.id as col_0_0_,
        member1_.nickname as col_1_0_,
        member1_.profile_image as col_2_0_,
        review0_.image as col_3_0_,
        review0_.rating as col_4_0_,
        review0_.content as col_5_0_,
        review0_.re_buy as col_6_0_,
        review0_.favorite_count as col_7_0_,
        reviewfavo2_.favorite as col_8_0_,
        review0_.created_at as col_9_0_ 
    from
        review review0_ 
    inner join
        member member1_ 
            on review0_.member_id=member1_.id 
    left outer join
        review_favorite reviewfavo2_ 
            on review0_.id=reviewfavo2_.review_id 
            and (
                reviewfavo2_.member_id=?
            ) 
    where
        review0_.product_id=? 
    order by
        review0_.created_at desc,
        review0_.id desc limit ?
Hibernate: 
    select
        reviewtag0_.id as id1_11_0_,
        review1_.id as id1_9_1_,
        tag2_.id as id1_12_2_,
        reviewtag0_.review_id as review_i2_11_0_,
        reviewtag0_.tag_id as tag_id3_11_0_,
        review1_.content as content2_9_1_,
        review1_.created_at as created_3_9_1_,
        review1_.favorite_count as favorite4_9_1_,
        review1_.image as image5_9_1_,
        review1_.member_id as member_i8_9_1_,
        review1_.product_id as product_9_9_1_,
        review1_.rating as rating6_9_1_,
        review1_.re_buy as re_buy7_9_1_,
        tag2_.name as name2_12_2_,
        tag2_.tag_type as tag_type3_12_2_ 
    from
        review_tag reviewtag0_ 
    inner join
        review review1_ 
            on reviewtag0_.review_id=review1_.id 
    inner join
        tag tag2_ 
            on reviewtag0_.tag_id=tag2_.id 
    where
        reviewtag0_.review_id in (
            ? , ? , ?
        )

응답 데이터

{
    "reviews": [
        {
            "id": 3,
            "userName": "member3",
            "profileImage": "www.member3.com",
            "image": "3.png",
            "rating": 3,
            "tags": [
                {
                    "id": 1,
                    "name": "맛있어요",
                    "tagType": "TASTE"
                },
                {
                    "id": 2,
                    "name": "간식",
                    "tagType": "ETC"
                },
                {
                    "id": 5,
                    "name": "갓성비",
                    "tagType": "QUANTITY"
                }
            ],
            "content": "test",
            "rebuy": false,
            "favoriteCount": 0,
            "favorite": false,
            "createdAt": "2023-10-27T02:04:45.914167"
        },
        {
            "id": 2,
            "userName": "member2",
            "profileImage": "www.member2.com",
            "image": "2.png",
            "rating": 4,
            "tags": [
                {
                    "id": 1,
                    "name": "맛있어요",
                    "tagType": "TASTE"
                },
                {
                    "id": 3,
                    "name": "단짠딴짠",
                    "tagType": "TASTE"
                },
                {
                    "id": 5,
                    "name": "갓성비",
                    "tagType": "QUANTITY"
                }
            ],
            "content": "test",
            "rebuy": true,
            "favoriteCount": 0,
            "favorite": false,
            "createdAt": "2023-10-27T02:04:45.884962"
        },
        {
            "id": 1,
            "userName": "member1",
            "profileImage": "www.member1.com",
            "image": "1.png",
            "rating": 2,
            "tags": [
                {
                    "id": 1,
                    "name": "맛있어요",
                    "tagType": "TASTE"
                },
                {
                    "id": 4,
                    "name": "아침식사",
                    "tagType": "ETC"
                }
            ],
            "content": "test",
            "rebuy": true,
            "favoriteCount": 0,
            "favorite": false,
            "createdAt": "2023-10-27T02:04:45.836016"
        }
    ],
    "hasNext": false
}

일정

• 추정 시간: 2