fix:学习记录查询/导出接口中，学习时长条件查询重新赋值补全实体类解耦逻辑，避免影响原表数据

servers/boe-server-all/src/main/java/com/xboe/school/study/service/impl/StudyCourseServiceImpl.java

@@ -30,6 +30,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.stereotype.Service;
 
+import javax.persistence.EntityManager;
 import javax.transaction.Transactional;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
@@ -100,6 +101,13 @@ public class StudyCourseServiceImpl implements IStudyCourseService{
 	@Autowired(required = false)
 	ICourseStudySearch esSearch;//对ES的处理
 
+	/**
+	 * 用于避免JPA查询后修改entity实体字段，自动更新到数据库
+	 */
+	@Autowired
+	private EntityManager entityManager;
+
+
 	@Override
 	public StudyCourse findByCourseIdAndAid(String courseId, String aid) {
 		//加上排序，如果是多条学习记录，只会取最新的一条
@@ -219,6 +227,8 @@ public class StudyCourseServiceImpl implements IStudyCourseService{
 				String queryStartTime = sc.getQueryStartTime();
 				String queryFinishTime = sc.getQueryFinishTime();
 				for (StudyCourse studyCourse : studyCourses) {
+					// 实体类解耦
+					entityManager.detach(studyCourse);
 					// 解析查询时间范围
 					LocalDate startDate = LocalDate.parse(queryStartTime);
 					LocalDate endDate = LocalDate.parse(queryFinishTime);
@@ -860,6 +870,8 @@ public class StudyCourseServiceImpl implements IStudyCourseService{
 				String queryStartTime = sc.getQueryStartTime();
 				String queryFinishTime = sc.getQueryFinishTime();
 				for (StudyCourse studyCourse : studyCourses) {
+					// 实体类解耦
+					entityManager.detach(studyCourse);
 					// 解析查询时间范围
 					LocalDate startDate = LocalDate.parse(queryStartTime);
 					LocalDate endDate = LocalDate.parse(queryFinishTime);