diff --git a/main.py b/main.py
index f4c8255..1fa1655 100644
--- a/main.py
+++ b/main.py
@@ -72,7 +72,7 @@ def process_gpx_files(tx: Connection):
         owner = os.path.split(filepath)[-1].split('_workout-')[0]
         filename = f'workout-{os.path.split(filepath)[-1].split("_workout-")[1]}'
         print(f'Processing {filename}')
-        if list(db.execute(text('select exists(select from training where owner = :owner and filename = :filename)'),
+        if list(tx.execute(text('select exists(select from training where owner = :owner and filename = :filename)'),
                 dict(owner=owner, filename=filename,),),)[0][0]:
             os.remove(filepath)
             continue
@@ -80,7 +80,7 @@ def process_gpx_files(tx: Connection):
             gpx_file = gpxpy.parse(f)
             if gpx_file.creator != 'FitoTrack':
                 raise ValueError('gpx file not generated by the FitoTrack app')
-            training_id = list(db.execute(
+            training_id = list(tx.execute(
                 text("""
                     insert into training(owner, filename, type, description, moving_time, stopped_time, moving_distance, stopped_distance) values 
                     (:owner, :filename, :type, :description, :moving_time, :stopped_time, :moving_distance, :stopped_distance) returning id
@@ -97,7 +97,7 @@ def process_gpx_files(tx: Connection):
             for track in gpx_file.tracks:
                 for segment in track.segments:
                     for point in segment.points:
-                        db.execute(text("""
+                        tx.execute(text("""
                             insert into training_data(training_id, t, geog, speed, elevation)
                                 values (:training_id, :t, :geog, :speed, :elevation)
                             """),