[feat] 인덱스를 통한 조회로 개수 count

1. 인덱스 생성후 created at으로 쿼리 타기
2. count(h) 보다 count *가 조회성능이 더 빠르기 때문에  변경 ( B tree 요소까지 접근 안해도 인덱스만 조회하면 되서 빠른거다 )

Author: hellozo0

src/main/java/com/moddy/server/domain/hair_model_application/repository/HairModelApplicationJpaRepository.java

@@ -4,8 +4,11 @@
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
+import java.time.LocalDateTime;
 import java.util.List;
 import java.util.Optional;
 
@@ -19,4 +22,7 @@ public interface HairModelApplicationJpaRepository extends JpaRepository<HairMod
 
     List<HairModelApplication> findAllByModelId(Long modelId);
 
+    @Query("SELECT COUNT(*) FROM HairModelApplication h WHERE h.createdAt >= :startDate AND h.createdAt < :endDate")
+    long countNonExpiredApplications(@Param("startDate") LocalDateTime startDate, @Param("endDate") LocalDateTime endDate);
+
 }

src/main/java/com/moddy/server/service/application/HairModelApplicationRetrieveService.java

@@ -28,6 +28,8 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.time.LocalDate;
+import java.time.LocalDateTime;
 import java.util.Comparator;
 import java.util.List;
 import java.util.stream.Collectors;
@@ -138,10 +140,7 @@ private Page<HairModelApplication> findApplicationsByPaging(final int page, fina
         PageRequest pageRequest = PageRequest.of(page - 1, size, Sort.by(Sort.Direction.DESC, "createdAt"));
         Page<HairModelApplication> applicationPage = hairModelApplicationJpaRepository.findAll(pageRequest);
 
-        long nonExpiredCount = hairModelApplicationJpaRepository.findAll()
-                    .stream()
-                    .filter(application -> !application.isExpired())
-                    .count();
+        long nonExpiredCount = hairModelApplicationJpaRepository.countNonExpiredApplications(LocalDate.now().minusDays(13).atStartOfDay(), LocalDate.now().plusDays(1).atStartOfDay());
 
         Page<HairModelApplication> nonExpiredApplications = applicationPage
                 .stream()