diff --git a/db/chat_log_db.py b/db/chat_log_db.py
index d1c7407..75671f6 100755
--- a/db/chat_log_db.py
+++ b/db/chat_log_db.py
@@ -156,7 +156,7 @@ def init_db():
                     product_title VARCHAR(512) DEFAULT '',
                     amount      DECIMAL(10,2) DEFAULT 0,
                     quantity    INTEGER DEFAULT 0,
-                    buyer_note  TEXT DEFAULT '',
+                    buyer_note  TEXT,
                     created_at  DATETIME NOT NULL,
                     updated_at  DATETIME NOT NULL
                 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4