refactor: 도움돼요 토글 비관적 락 제거 및 CQRS 구조 개선

src/main/java/com/ongil/backend/domain/review/controller/ReviewController.java

@@ -107,7 +107,7 @@ public DataResponse<ReviewHelpfulResponse> toggleHelpful(
 		@PathVariable Long reviewId,
 		@AuthenticationPrincipal Long userId
 	) {
-		ReviewHelpfulResponse response = reviewQueryService.toggleHelpful(reviewId, userId);
+		ReviewHelpfulResponse response = reviewCommandService.toggleHelpful(reviewId, userId);
 		return DataResponse.from(response);
 	}
 

src/main/java/com/ongil/backend/domain/review/entity/Review.java

@@ -121,16 +121,6 @@ public class Review extends BaseEntity {
 	@JoinColumn(name = "product_id", nullable = false)
 	private Product product;
 
-	public void incrementHelpfulCount() {
-		this.helpfulCount++;
-	}
-
-	public void decrementHelpfulCount() {
-		if (this.helpfulCount > 0) {
-			this.helpfulCount--;
-		}
-	}
-
 	public void updateStep1(int rating, SizeAnswer sizeAnswer, ColorAnswer colorAnswer, MaterialAnswer materialAnswer) {
 		this.rating = rating;
 		this.sizeAnswer = sizeAnswer;

src/main/java/com/ongil/backend/domain/review/repository/ReviewRepository.java

@@ -8,7 +8,6 @@
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
-import org.springframework.data.jpa.repository.Lock;
 import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
@@ -17,8 +16,6 @@
 import com.ongil.backend.domain.review.enums.ReviewStatus;
 import com.ongil.backend.domain.review.enums.ReviewType;
 
-import jakarta.persistence.LockModeType;
-
 public interface ReviewRepository extends JpaRepository<Review, Long> {
 
 	// 상품별 리뷰 목록 조회 (필터 없음)
@@ -189,9 +186,13 @@ List<Long> findReviewedOrderItemIds(
 		@Param("reviewType") ReviewType reviewType
 	);
 
-	@Lock(LockModeType.PESSIMISTIC_WRITE)
-	@Query("SELECT r FROM Review r WHERE r.id = :reviewId")
-	Optional<Review> findByIdWithLock(@Param("reviewId") Long reviewId);
+	@Modifying(clearAutomatically = true)
+	@Query("UPDATE Review r SET r.helpfulCount = r.helpfulCount + 1 WHERE r.id = :reviewId")
+	void incrementHelpfulCount(@Param("reviewId") Long reviewId);
+
+	@Modifying(clearAutomatically = true)
+	@Query("UPDATE Review r SET r.helpfulCount = r.helpfulCount - 1 WHERE r.id = :reviewId AND r.helpfulCount > 0")
+	void decrementHelpfulCount(@Param("reviewId") Long reviewId);
 
 	@Modifying
 	@Query("DELETE FROM Review r WHERE r.reviewStatus = 'DRAFT' AND r.createdAt < :threshold")

src/main/java/com/ongil/backend/domain/review/service/ReviewCommandService.java

@@ -17,13 +17,16 @@
 import com.ongil.backend.domain.review.dto.request.ReviewStep2MaterialRequest;
 import com.ongil.backend.domain.review.dto.request.ReviewStep2SizeRequest;
 import com.ongil.backend.domain.review.dto.response.AiReviewResponse;
+import com.ongil.backend.domain.review.dto.response.ReviewHelpfulResponse;
 import com.ongil.backend.domain.review.dto.response.ReviewStep1Response;
 import com.ongil.backend.domain.review.entity.Review;
+import com.ongil.backend.domain.review.entity.ReviewHelpful;
 import com.ongil.backend.domain.review.enums.ClothingCategory;
 import com.ongil.backend.domain.review.enums.MaterialAnswer;
 import com.ongil.backend.domain.review.enums.MaterialFeatureType;
 import com.ongil.backend.domain.review.enums.ReviewStatus;
 import com.ongil.backend.domain.review.enums.ReviewType;
+import com.ongil.backend.domain.review.repository.ReviewHelpfulRepository;
 import com.ongil.backend.domain.review.repository.ReviewRepository;
 import com.ongil.backend.domain.review.validator.ReviewValidator;
 import com.ongil.backend.domain.user.entity.User;
@@ -42,6 +45,7 @@ public class ReviewCommandService {
 	private static final int REVIEW_REWARD_POINTS = 500;
 
 	private final ReviewRepository reviewRepository;
+	private final ReviewHelpfulRepository reviewHelpfulRepository;
 	private final UserRepository userRepository;
 	private final OrderItemRepository orderItemRepository;
 	private final ProductRepository productRepository;
@@ -177,6 +181,36 @@ public void submitReview(Long userId, Long reviewId, ReviewFinalSubmitRequest re
 		productRepository.updateReviewStats(review.getProduct().getId());
 	}
 
+	public ReviewHelpfulResponse toggleHelpful(Long reviewId, Long userId) {
+		Review review = reviewRepository.findById(reviewId)
+			.orElseThrow(() -> new EntityNotFoundException(ErrorCode.REVIEW_NOT_FOUND));
+
+		boolean exists = reviewHelpfulRepository.existsByReviewIdAndUserId(reviewId, userId);
+
+		if (exists) {
+			reviewHelpfulRepository.deleteByReviewIdAndUserId(reviewId, userId);
+			reviewRepository.decrementHelpfulCount(reviewId);
+		} else {
+			User user = getUserOrThrow(userId);
+			ReviewHelpful helpful = ReviewHelpful.builder()
+				.review(review)
+				.user(user)
+				.build();
+			reviewHelpfulRepository.save(helpful);
+			reviewRepository.incrementHelpfulCount(reviewId);
+		}
+
+		int updatedCount = exists
+			? Math.max(0, review.getHelpfulCount() - 1)
+			: review.getHelpfulCount() + 1;
+
+		return ReviewHelpfulResponse.builder()
+			.reviewId(reviewId)
+			.isHelpful(!exists)
+			.helpfulCount(updatedCount)
+			.build();
+	}
+
 	private Review getReviewOrThrow(Long reviewId) {
 		return reviewRepository.findById(reviewId)
 			.orElseThrow(() -> new EntityNotFoundException(ErrorCode.REVIEW_NOT_FOUND));

src/main/java/com/ongil/backend/domain/review/service/ReviewQueryService.java

@@ -21,7 +21,6 @@
 import com.ongil.backend.domain.review.dto.request.ReviewListRequest;
 import com.ongil.backend.domain.review.dto.response.*;
 import com.ongil.backend.domain.review.entity.Review;
-import com.ongil.backend.domain.review.entity.ReviewHelpful;
 import com.ongil.backend.domain.review.enums.ColorAnswer;
 import com.ongil.backend.domain.review.enums.MaterialAnswer;
 import com.ongil.backend.domain.review.enums.ReviewSortType;
@@ -215,36 +214,6 @@ public int getPendingReviewCount(Long userId) {
 		return count;
 	}
 
-	// 6. 리뷰 도움돼요 토글
-	@Transactional
-	public ReviewHelpfulResponse toggleHelpful(Long reviewId, Long userId) {
-		// 리뷰에 대한 PESSIMISTIC WRITE 락 획득
-		Review review = reviewRepository.findByIdWithLock(reviewId)
-			.orElseThrow(() -> new EntityNotFoundException(ErrorCode.REVIEW_NOT_FOUND));
-
-		User user = getUserOrThrow(userId);
-
-		boolean exists = reviewHelpfulRepository.existsByReviewIdAndUserId(reviewId, userId);
-
-		if (exists) {
-			reviewHelpfulRepository.deleteByReviewIdAndUserId(reviewId, userId);
-			review.decrementHelpfulCount();
-		} else {
-			ReviewHelpful helpful = ReviewHelpful.builder()
-				.review(review)
-				.user(user)
-				.build();
-			reviewHelpfulRepository.save(helpful);
-			review.incrementHelpfulCount();
-		}
-
-		return ReviewHelpfulResponse.builder()
-			.reviewId(reviewId)
-			.isHelpful(!exists)
-			.helpfulCount(review.getHelpfulCount())
-			.build();
-	}
-
 	// 정렬 기준에 따른 Pageable 생성
 	private Pageable createPageable(int page, int size, ReviewSortType sortType) {
 		if (size <= 0) size = 10;