diff --git a/update_db.py b/update_db.py
index 5f43424..3d551a0 100644
--- a/update_db.py
+++ b/update_db.py
@@ -141,7 +141,6 @@ def update_tables (
         api_data:           list[VideoResult],
         now:                datetime,
 ) -> None:
-    video_ids: list[int] = []
     for datum in api_data:
         tag_names: list[str] = datum['tags'].split ()
         video = VideoDto (code          = datum['contentId'],
@@ -150,7 +149,6 @@ def update_tables (
                           uploaded_at   = datetime.fromisoformat (datum['startTime']))
         video_dao.upsert (video, False)
         if video.id_ is not None:
-            video_ids.append (video.id_)
             video_history = VideoHistoryDto (video_id       = video.id_,
                                              fetched_at     = now,
                                              views_count    = datum['viewCounter'])
@@ -160,7 +158,7 @@ def update_tables (
             for vt in video_tags:
                 tag = tag_dao.find (vt.tag_id)
                 if (tag is not None
-                        and (tag.name.upper () not in [tn.upper () for tn in tag_names])
+                        and (tag.name.upper () not in map (str.upper, tag_names))
                         and (tag.id_ is not None)):
                     tag_ids.append (tag.id_)
             video_tag_dao.untag_all (video.id_, tag_ids, now)
@@ -535,7 +533,7 @@ class VideoTagDao:
                       video_tags
                     WHERE
                       video_id = %s
-                      AND (untagged_at IS NULL)
+                      AND untagged_at IS NULL
                     ORDER BY
                       id""", (video_id,))
             print (c._executed)
@@ -562,7 +560,8 @@ class VideoTagDao:
                       video_tags
                     WHERE
                       video_id = %s
-                      AND tag_id = %s""", (video_id, tag_id))
+                      AND tag_id = %s
+                      AND untagged_at IS NULL""", (video_id, tag_id))
             print (c._executed)
             row = cast (VideoTagRow, c.fetchone ())
             if row is None: