[jira] [Created] (ARROW-13784) PyArrow from_arrays should return a schema when array is empty but names is not

[Abderrahmane Jaidi (Jira)]

Abderrahmane Jaidi created ARROW-13784:
------------------------------------------

             Summary: PyArrow from_arrays should return a schema when array is 
empty but names is not
                 Key: ARROW-13784
                 URL: https://issues.apache.org/jira/browse/ARROW-13784
             Project: Apache Arrow
          Issue Type: Bug
          Components: Python
    Affects Versions: 4.0.1
            Reporter: Abderrahmane Jaidi


The `Table.from_arrays` method returns an empty schema when supplying an empty 
arrays list but providing column names. As a result, the subsequent `to_pandas` 
method returns an empty data frame with no column names.

```

{{import pyarrow as pa}}

{{arrays = []}}

{{cols_names = ["col1", "col2"]}}

{{table = pa.Table.from_arrays(arrays=arrays, names=cols_names)}}

{{table.schema  # returns nothing}}

{{df = table.to_pandas()}}

{{df.head()}}

{{Empty DataFrame
Columns: []
Index: [] # Expected column names to be visible here}}

```

I assume that this is because a schema cannot be built without data types?



--
This message was sent by Atlassian Jira
(v8.3.4#803005)