Tested in big data set

buisnesslogic/src/main/java/com/plannaplan/services/UserService.java

@@ -154,6 +154,10 @@ public class UserService {
         return this.repo.getAllByRole(UserRoles.ADMIN).size() > 0;
     }
 
+    public void saveAll(List<User> users) {
+        this.repo.saveAll(users);
+    }
+
     /**
      * get students sorted by their ranking
      *