优化

src/main/java/com/template/services/impl/WelcomeStudentServiceImpl.java

@@ -161,7 +161,7 @@ public class WelcomeStudentServiceImpl extends ServiceImpl<WelcomeStudentMapper,
                 .or()
                 .eq(StringUtils.hasText(cardId), "card_id", cardId));
         List<WelcomeStudent> result = welcomeStudentMapper.selectList(queryWrapper);
-        return (result != null && result.size() > 0) ? result.get(0) : new WelcomeStudent();
+        return (result != null && result.size() > 0) ? result.get(0) : null;
     }
 
     @Override