feat: gemini dingo/data/datasource/local.py

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: shijinpjlab

dingo/data/datasource/local.py

@@ -175,7 +175,7 @@ def _load_parquet_file(self, path: str) -> Generator[str, None, None]:
                 batch_dict = batch.to_pydict()
 
                 # 获取批次中的行数
-                num_rows = len(batch_dict[next(iter(batch_dict))])
+                num_rows = len(next(iter(batch_dict.values()))) if batch_dict else 0
 
                 # 逐行处理
                 for i in range(num_rows):