Fix databricks_sql hook query failing on empty result for return_tuple

airflow/providers/databricks/hooks/databricks_sql.py

@@ -280,6 +280,8 @@ def _make_common_data_structure(self, result: Sequence[Row] | Row) -> list[tuple
         # instantiated namedtuple, and will never do: https://github.com/python/mypy/issues/848
         if isinstance(result, list):
             rows: list[Row] = result
+            if not rows:
+                return []
             rows_fields = rows[0].__fields__
             rows_object = namedtuple("Row", rows_fields)  # type: ignore[misc]
             return cast(List[tuple], [rows_object(*row) for row in rows])

tests/providers/databricks/hooks/test_databricks_sql.py

@@ -200,11 +200,23 @@ def get_cursor_descriptions(fields: list[str]) -> list[tuple[str]]:
             ["select * from test.test"],
             True,
             [["id", "value"]],
-            (Row(id=1, value=2),),
+            ([Row(id=1, value=2)],),
             [[("id",), ("value",)]],
-            SerializableRow(1, 2),
+            [SerializableRow(1, 2)],
             id="The return_last set and no split statements set on single query in string",
         ),
+        pytest.param(
+            True,
+            False,
+            "select * from test.test",
+            ["select * from test.test"],
+            True,
+            [["id", "value"]],
+            ([],),
+            [[("id",), ("value",)]],
+            [],
+            id="Empty list",
+        ),
     ],
 )
 def test_query(