diff --git a/ceilometer/storage/__init__.py b/ceilometer/storage/__init__.py
index 7dab32037..ca273f768 100644
--- a/ceilometer/storage/__init__.py
+++ b/ceilometer/storage/__init__.py
@@ -57,7 +57,8 @@ def register_opts(conf):
 def get_engine(conf):
     """Load the configured engine and return an instance."""
     if conf.database_connection:
-        conf.database.connection = conf.database_connection
+        conf.set_override('connection', conf.database_connection,
+                          group='database')
     engine_name = urlparse.urlparse(conf.database.connection).scheme
     LOG.debug('looking for %r driver in %r',
               engine_name, STORAGE_ENGINE_NAMESPACE)
diff --git a/ceilometer/storage/impl_mongodb.py b/ceilometer/storage/impl_mongodb.py
index 6767d507a..38f040dea 100644
--- a/ceilometer/storage/impl_mongodb.py
+++ b/ceilometer/storage/impl_mongodb.py
@@ -322,7 +322,6 @@ class Connection(base.Connection):
         # a new key '_id').
         record = copy.copy(data)
         self.db.meter.insert(record)
-        return
 
     def get_users(self, source=None):
         """Return an iterable of user id strings.
diff --git a/ceilometer/storage/impl_sqlalchemy.py b/ceilometer/storage/impl_sqlalchemy.py
index 107e4fcd0..91c1e04c3 100644
--- a/ceilometer/storage/impl_sqlalchemy.py
+++ b/ceilometer/storage/impl_sqlalchemy.py
@@ -212,8 +212,6 @@ class Connection(base.Connection):
             meter.message_id = data['message_id']
             session.flush()
 
-        return
-
     def get_users(self, source=None):
         """Return an iterable of user id strings.