diff --git a/api/chat.py b/api/chat.py
index 9ea1ad7..50da192 100644
--- a/api/chat.py
+++ b/api/chat.py
@@ -246,13 +246,10 @@ class Room(blivedm.BLiveClient):
             return
         self.send_message_if(
             lambda client: client.auto_translate,
-            Command.UPDATE_TRANSLATION,
-            [
-                # 0: id
+            Command.UPDATE_TRANSLATION, make_translation_message(
                 msg_id,
-                # 1: translation
                 translation
-            ]
+            )
         )
 
 
@@ -289,6 +286,15 @@ def make_text_message(avatar_url, timestamp, author_name, author_type, content,
     ]
 
 
+def make_translation_message(msg_id, translation):
+    return [
+        # 0: id
+        msg_id,
+        # 1: translation
+        translation
+    ]
+
+
 class RoomManager:
     def __init__(self):
         self._rooms: Dict[int, Room] = {}
diff --git a/models/avatar.py b/models/avatar.py
index 6ca23cb..5668343 100644
--- a/models/avatar.py
+++ b/models/avatar.py
@@ -200,5 +200,5 @@ def _update_avatar_cache_in_database(user_id, avatar_url):
 class BilibiliUser(models.database.OrmBase):
     __tablename__ = 'bilibili_users'
     uid = sqlalchemy.Column(sqlalchemy.Integer, primary_key=True)
-    avatar_url = sqlalchemy.Column(sqlalchemy.Text)
+    avatar_url = sqlalchemy.Column(sqlalchemy.String(100))
     update_time = sqlalchemy.Column(sqlalchemy.DateTime)