implement get_creation_statastics for sqlite backend

src/aiida/storage/psql_dos/orm/querybuilder/main.py

@@ -33,6 +33,7 @@
 from aiida.common.exceptions import NotExistent
 from aiida.orm.entities import EntityTypes
 from aiida.orm.implementation.querybuilder import QUERYBUILD_LOGGER, BackendQueryBuilder, QueryDictType
+from aiida.storage import psql_dos, sqlite_dos
 
 from .joiner import JoinReturn, SqlaJoiner
 
@@ -798,8 +799,26 @@ def get_creation_statistics(self, user_pk: Optional[int] = None) -> Dict[str, An
 
         total_query = session.query(self.Node)
         types_query = session.query(self.Node.node_type.label('typestring'), sa_func.count(self.Node.id))
+
+        backend_class = self._backend.__class__
+        date_format = '%Y-%m-%d'
+
+        if backend_class == sqlite_dos.backend.SqliteDosStorage:
+            cday = sa_func.strftime(date_format, sa_func.datetime(self.Node.ctime, 'localtime'))
+
+            def date_to_str(d):
+                return d
+
+        elif backend_class == psql_dos.backend.PsqlDosBackend:
+            cday = sa_func.date_trunc('day', self.Node.ctime)
+
+            def date_to_str(d):
+                return d.strftime(date_format)
+
+        else:
+            raise NotImplementedError(f'unsupported backend: {backend_class}')
         stat_query = session.query(
-            sa_func.date_trunc('day', self.Node.ctime).label('cday'),
+            cday.label('cday'),
             sa_func.count(self.Node.id),
         )
 
@@ -817,7 +836,7 @@ def get_creation_statistics(self, user_pk: Optional[int] = None) -> Dict[str, An
         # Nodes created per day
         stat = stat_query.group_by('cday').order_by('cday').all()
 
-        ctime_by_day = {_[0].strftime('%Y-%m-%d'): _[1] for _ in stat}
+        ctime_by_day = {date_to_str(entry[0]): entry[1] for entry in stat}
         retdict['ctime_by_day'] = ctime_by_day
 
         return retdict

tests/orm/test_querybuilder.py

@@ -1581,9 +1581,6 @@ class TestManager:
     def init_db(self, backend):
         self.backend = backend
 
-    # This fails with sqlite with:
-    # sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such function: date_trunc
-    @pytest.mark.requires_psql
     def test_statistics(self):
         """Test if the statistics query works properly.
 
@@ -1620,9 +1617,6 @@ def store_and_add(n, statistics):
 
         assert new_db_statistics == expected_db_statistics
 
-    # This fails with sqlite with:
-    # sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such function: date_trunc
-    @pytest.mark.requires_psql
     def test_statistics_default_class(self):
         """Test if the statistics query works properly.
 

tests/restapi/test_statistics.py

@@ -33,10 +33,7 @@ def linearize_namespace(tree_namespace, linear_namespace=None):
     return linear_namespace
 
 
-# This test does not work with SQLite since it uses the `statistics` endpoint,
-# which uses `date_trunc` under the hood, which is not implemented in SQLite.
 @pytest.mark.usefixtures('populate_restapi_database')
-@pytest.mark.requires_psql
 def test_count_consistency(restapi_server, server_url):
     """Test the consistency in values between full_type_count and statistics"""
     server = restapi_server()