回测读取历史数据失败

回测时，下载数据成功，但是回测失败。 历史数据存在influxdb中，全局配置正确，数据已经下载到influxdb中。 报错信息如下：

Traceback (most recent call last): File "C:\Users\alien\AppData\Local\veighna_studio\Lib\threading.py", line 1041, in _bootstrap_inner self.run() ~~~~~~~~^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\threading.py", line 992, in run self._target(*self._args, **self._kwargs) ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\vnpy_ctabacktester\engine.py", line 186, in run_backtesting engine.load_data() ~~~~~~~~~~~~~~~~^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\vnpy_ctastrategy\backtesting.py", line 192, in load_data data: list[BarData] = load_bar_data( ~~~~~~~~~~~~~^ self.symbol, ^^^^^^^^^^^^ ...<3 lines>... end ^^^ ) ^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\vnpy_ctastrategy\backtesting.py", line 1108, in load_bar_data return database.load_bar_data(symbol, exchange, interval, start, end) # type: ignore ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\vnpy_influxdb\influxdb_database.py", line 282, in load_bar_data df: pd.DataFrame = pd.read_csv(result)[3:] ~~~~~~~~~~~^^^^^^^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\pandas\io\parsers\readers.py", line 1026, in read_csv return _read(filepath_or_buffer, kwds) File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\pandas\io\parsers\readers.py", line 620, in _read parser = TextFileReader(filepath_or_buffer, **kwds) File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\pandas\io\parsers\readers.py", line 1620, in init self._engine = self._make_engine(f, self.engine) ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\pandas\io\parsers\readers.py", line 1898, in _make_engine return mapping[engine](f, **self.options) ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^ File "C:\Users\alien\AppData\Local\veighna_studio\Lib\site-packages\pandas\io\parsers\c_parser_wrapper.py", line 93, in init self._reader = parsers.TextReader(src, **kwds) ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^ File "parsers.pyx", line 581, in pandas._libs.parsers.TextReader.cinit pandas.errors.EmptyDataError: No columns to parse from file