diff --git a/ads.py b/ads.py
index 0a6ab27..371fd4d 100644
--- a/ads.py
+++ b/ads.py
@@ -177,6 +177,8 @@ class AsyncDataSet:
         args: Dict[str, Any],
         where: Optional[Dict[str, Any]] = None,
     ) -> str | None:
+        if not args:
+            raise ValueError("Nothing to update. Empty dict given.")
         args['updated_at'] = str(datetime.now())
         affected = await self.update(table, args, where)
         if affected:
@@ -357,6 +359,7 @@ class TestAsyncDataSet(unittest.IsolatedAsyncioTestCase):
 
     async def test_update(self):
         await self.connector.insert("people", {"name": "John Doe", "age": 30})
+        await asyncio.sleep(2)
         await self.connector.update("people", {"age": 31}, {"name": "John Doe"})
         rec = await self.connector.get("people", {"name": "John Doe"})
         self.assertEqual(rec["age"], 31)
@@ -514,12 +517,13 @@ class TestAsyncDataSet(unittest.IsolatedAsyncioTestCase):
         self.assertEqual(count, 5)
 
     async def test_column_type_preservation(self):
-        data = {"name": "Test", "number": 42, "float": 3.14, "bool": True}
+        data = {"name": "Test", "number": 42, "float": 3.14, "bool": True,"bytes":b"data"}
         await self.connector.insert("types", data)
         rec = await self.connector.get("types", {"name": "Test"})
         self.assertIsInstance(rec["number"], int)
         self.assertIsInstance(rec["float"], float)
         self.assertIsInstance(rec["bool"], int)  # SQLite stores bool as int
+        self.assertIsInstance(rec["bytes"], bytes)  # SQLite stores bool as int
         self.assertEqual(rec["bool"], 1)
 
     async def test_empty_update(self):
@@ -540,5 +544,7 @@ class TestAsyncDataSet(unittest.IsolatedAsyncioTestCase):
         with self.assertRaises(aiosqlite.OperationalError):
             await self.connector.insert("invalid table name", {"name": "John"})
 
+
+
 if __name__ == "__main__":
     unittest.main()