def test_specify_columns_to_read(scalar_dataset, reader_factory):
    """Just a bunch of read and compares of all values to the expected values using the different reader pools"""
    with reader_factory(scalar_dataset.url, schema_fields=['id', 'float.*$']) as reader:
        sample = next(reader)
        assert set(sample._asdict().keys()) == {'id', 'float64'}
        assert sample.float64.size > 0
Just a bunch of read and compares of all values to the expected values using the different reader pools
petastorm/tests/test_parquet_reader.py