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1""" orc compat """
3import distutils
4from typing import TYPE_CHECKING, List, Optional
6from pandas._typing import FilePathOrBuffer
8from pandas.io.common import get_filepath_or_buffer
10if TYPE_CHECKING:
11 from pandas import DataFrame
14def read_orc(
15 path: FilePathOrBuffer, columns: Optional[List[str]] = None, **kwargs,
16) -> "DataFrame":
17 """
18 Load an ORC object from the file path, returning a DataFrame.
20 .. versionadded:: 1.0.0
22 Parameters
23 ----------
24 path : str, path object or file-like object
25 Any valid string path is acceptable. The string could be a URL. Valid
26 URL schemes include http, ftp, s3, and file. For file URLs, a host is
27 expected. A local file could be:
28 ``file://localhost/path/to/table.orc``.
30 If you want to pass in a path object, pandas accepts any
31 ``os.PathLike``.
33 By file-like object, we refer to objects with a ``read()`` method,
34 such as a file handler (e.g. via builtin ``open`` function)
35 or ``StringIO``.
36 columns : list, default None
37 If not None, only these columns will be read from the file.
38 **kwargs
39 Any additional kwargs are passed to pyarrow.
41 Returns
42 -------
43 DataFrame
44 """
46 # we require a newer version of pyarrow than we support for parquet
47 import pyarrow
49 if distutils.version.LooseVersion(pyarrow.__version__) < "0.13.0":
50 raise ImportError("pyarrow must be >= 0.13.0 for read_orc")
52 import pyarrow.orc
54 path, _, _, _ = get_filepath_or_buffer(path)
55 orc_file = pyarrow.orc.ORCFile(path)
56 result = orc_file.read(columns=columns, **kwargs).to_pandas()
57 return result