fix: Remove index requirement from some dataframe APIs

bigframes/bigquery/__init__.py

@@ -493,8 +493,8 @@ def vector_search(
     )
     if index_col_ids is not None:
         df = query._session.read_gbq(sql, index_col=index_col_ids)
+        df.index.names = index_labels
     else:
         df = query._session.read_gbq(sql)
-    df.index.names = index_labels
 
     return df

bigframes/core/eval.py

@@ -38,12 +38,15 @@ def eval(df: dataframe.DataFrame, expr: str, target: Optional[dataframe.DataFram
     Returns:
         Result of evaluation.
     """
-    index_resolver = {
-        vendored_pandas_eval_parsing.clean_column_name(str(name)): EvalSeries(
-            df.index.get_level_values(level).to_series()
-        )
-        for level, name in enumerate(df.index.names)
-    }
+    if df._has_index:
+        index_resolver = {
+            vendored_pandas_eval_parsing.clean_column_name(str(name)): EvalSeries(
+                df.index.get_level_values(level).to_series()
+            )
+            for level, name in enumerate(df.index.names)
+        }
+    else:
+        index_resolver = {}
     column_resolver = {
         vendored_pandas_eval_parsing.clean_column_name(str(name)): EvalSeries(series)
         for name, series in df.items()

bigframes/dataframe.py

@@ -768,7 +768,7 @@ def _apply_series_binop_axis_0(
         reverse: bool = False,
     ) -> DataFrame:
         bf_series = bigframes.core.convert.to_bf_series(
-            other, self.index, self._session
+            other, self.index if self._has_index else None, self._session
         )
         aligned_block, columns, expr_pairs = self._block._align_axis_0(
             bf_series._block, how=how
@@ -3179,6 +3179,7 @@ def to_gbq(
         clustering_columns: Union[pandas.Index, Iterable[typing.Hashable]] = (),
         labels: dict[str, str] = {},
     ) -> str:
+        index = index and self._has_index
         temp_table_ref = None
 
         if destination_table is None:

tests/system/small/test_null_index.py

@@ -21,6 +21,23 @@
 from tests.system.utils import skip_legacy_pandas
 
 
+def test_null_index_to_gbq(session, scalars_df_null_index, dataset_id_not_created):
+    dataset_id = dataset_id_not_created
+    destination_table = f"{dataset_id}.scalars_df_unindexed"
+
+    result_table = scalars_df_null_index.to_gbq(
+        destination_table, clustering_columns=["int64_col"]
+    )
+    assert (
+        result_table == destination_table
+        if destination_table
+        else result_table is not None
+    )
+
+    loaded_scalars_df_index = session.read_gbq(result_table)
+    assert not loaded_scalars_df_index.empty
+
+
 def test_null_index_materialize(scalars_df_null_index, scalars_pandas_df_default_index):
     bf_result = scalars_df_null_index.to_pandas()
     pd.testing.assert_frame_equal(
@@ -83,6 +100,23 @@ def test_null_index_aggregate(scalars_df_null_index, scalars_pandas_df_default_i
     )
 
 
+def test_null_index_binop_series_axis_0(
+    scalars_df_null_index, scalars_pandas_df_default_index
+):
+    bf_result = (
+        scalars_df_null_index[["int64_col", "int64_too"]]
+        .add(scalars_df_null_index["int64_col"], axis=0)
+        .to_pandas()
+    )
+    pd_result = scalars_pandas_df_default_index[["int64_col", "int64_too"]].add(
+        scalars_pandas_df_default_index.int64_col, axis=0
+    )
+
+    pd.testing.assert_frame_equal(
+        bf_result, pd_result, check_dtype=False, check_index_type=False
+    )
+
+
 def test_null_index_groupby_aggregate(
     scalars_df_null_index, scalars_pandas_df_default_index
 ):
@@ -139,6 +173,25 @@ def test_null_index_merge_left_null_index_object(
     assert got.shape == expected.shape
 
 
+@skip_legacy_pandas
+@pytest.mark.parametrize(
+    ("expr",),
+    [
+        ("new_col = int64_col + int64_too",),
+        ("new_col = (rowindex > 3) | bool_col",),
+        ("int64_too = bool_col\nnew_col2 = rowindex",),
+    ],
+)
+def test_null_index_df_eval(
+    scalars_df_null_index, scalars_pandas_df_default_index, expr
+):
+
+    bf_result = scalars_df_null_index.eval(expr).to_pandas()
+    pd_result = scalars_pandas_df_default_index.eval(expr)
+
+    pd.testing.assert_frame_equal(bf_result, pd_result, check_index_type=False)
+
+
 def test_null_index_merge_right_null_index_object(
     scalars_df_null_index, scalars_df_default_index, scalars_pandas_df_default_index
 ):