diff --git a/src/covid19/blueprints/who/who_model.py b/src/covid19/blueprints/who/who_model.py
index 298b7cae95c376171cdb1b446d8910d64c15f7b6..7a52374f7fe2e8e348ed06a410a5f8f90e7db46b 100644
--- a/src/covid19/blueprints/who/who_model.py
+++ b/src/covid19/blueprints/who/who_model.py
@@ -1,7 +1,8 @@
 from sqlalchemy import and_, func
 from datetime import date
 from database import db, ITEMS_PER_PAGE
-from sqlalchemy.orm import joinedload, load_only
+from sqlalchemy.orm import joinedload, load_only, defaultload, defer, undefer, query_expression, subqueryload
+from sqlalchemy.sql import select
 from covid19.blueprints.application.application_model import ApplicationDateReported, ApplicationRegion
 
 
@@ -59,7 +60,6 @@ class WhoDateReported(ApplicationDateReported):
             year_week=my_year_week
         )
 
-
 class WhoRegion(ApplicationRegion):
     __tablename__ = 'who_country_region'
     __mapper_args__ = {'concrete': True}
@@ -199,14 +199,6 @@ class WhoData(db.Model):
         cascade='save-update',
         order_by='asc(WhoCountry.country)')
 
-    @classmethod
-    def get_datum_of_all_who_data(cls):
-        return db.session.query(WhoData)\
-            .join(WhoDateReported, WhoData.date_reported)\
-            .options(load_only(WhoDateReported.date_reported))\
-            .group_by(WhoDateReported.date_reported)\
-            .all()
-
     @classmethod
     def remove_all(cls):
         for one in cls.get_all():
@@ -366,3 +358,15 @@ class WhoData(db.Model):
         ).order_by(
             cls.deaths_cumulative.desc()
         ).paginate(page, per_page=ITEMS_PER_PAGE)
+
+    @classmethod
+    def get_datum_of_all_who_data(cls):
+        return db.session.query(cls).options(subqueryload("date_reported").load_only("date_reported_import_str"))
+
+    @classmethod
+    def get_datum_of_all_who_data2(cls):
+        stmt = (
+            select(WhoData,WhoDateReported).join(WhoData.date_reported).filter(WhoData.date_reported_id == WhoDateReported.id)\
+            .options(defaultload("someattr").defer("some_column"))
+        )
+        return db.session.query()
\ No newline at end of file
diff --git a/src/covid19/blueprints/who_test/who_test_views.py b/src/covid19/blueprints/who_test/who_test_views.py
index abcc2089f9477d8b626f7303c06f9fc4c67c3538..38fe69d3d71350bb3776cb46c5d0e3c68cd13615 100644
--- a/src/covid19/blueprints/who_test/who_test_views.py
+++ b/src/covid19/blueprints/who_test/who_test_views.py
@@ -87,7 +87,7 @@ def url_who_test_who_data_get_datum_of_all_who_data():
     app.logger.info("url_who_test_who_data_get_datum_of_all_who_data - DONE: WhoData.get_datum_of_all_who_data()")
     flash("url_who_test_who_data_get_datum_of_all_who_data - START: WhoData.get_datum_of_all_who_data()")
     for datum in WhoData.get_datum_of_all_who_data():
-        app.logger.info(str(datum.date_reported))
+        app.logger.info(str(datum))
     flash("url_who_test_who_data_get_datum_of_all_who_data - DONE: WhoData.get_datum_of_all_who_data()")
     app.logger.info("url_who_test_who_data_get_datum_of_all_who_data - DONE: WhoData.get_datum_of_all_who_data()")
     return redirect(url_for('who_test.url_who_test_tests'))