diff --git a/src/cs50/sql.py b/src/cs50/sql.py
index 3e695d6..25ce30e 100644
--- a/src/cs50/sql.py
+++ b/src/cs50/sql.py
@@ -284,7 +284,7 @@ def execute(self, sql, *args, **kwargs):
                 # Disconnect later
                 @flask.current_app.teardown_appcontext
                 def shutdown_session(exception=None):
-                    if flask.g._connection:
+                    if hasattr(flask.g, "_connection") and flask.g._connection:
                         flask.g._connection.close()
 
             # If no connection for context yet