fix(mssql): avoid trying to return a resultset for DML queries with n…

…ot resultset (#24999)

superset/db_engine_specs/mssql.py

@@ -141,6 +141,8 @@ def convert_dttm(
     def fetch_data(
         cls, cursor: Any, limit: Optional[int] = None
     ) -> list[tuple[Any, ...]]:
+        if not cursor.description:
+            return []
         data = super().fetch_data(cursor, limit)
         # Lists of `pyodbc.Row` need to be unpacked further
         return cls.pyodbc_rows_to_tuples(data)

tests/unit_tests/db_engine_specs/test_mssql.py

@@ -157,6 +157,14 @@ def test_extract_error_message() -> None:
     assert expected_message == error_message
 
 
+def test_fetch_data_no_description() -> None:
+    from superset.db_engine_specs.mssql import MssqlEngineSpec
+
+    cursor = mock.MagicMock()
+    cursor.description = []
+    assert MssqlEngineSpec.fetch_data(cursor) == []
+
+
 def test_fetch_data() -> None:
     from superset.db_engine_specs.base import BaseEngineSpec
     from superset.db_engine_specs.mssql import MssqlEngineSpec
@@ -166,9 +174,10 @@ def test_fetch_data() -> None:
         "pyodbc_rows_to_tuples",
         return_value="converted",
     ) as mock_pyodbc_rows_to_tuples:
+        cursor = mock.MagicMock()
         data = [(1, "foo")]
         with mock.patch.object(BaseEngineSpec, "fetch_data", return_value=data):
-            result = MssqlEngineSpec.fetch_data(None, 0)
+            result = MssqlEngineSpec.fetch_data(cursor, 0)
             mock_pyodbc_rows_to_tuples.assert_called_once_with(data)
             assert result == "converted"