How to support Apache Parquet data?

[kou]

151 added a dataset that uses Apache Parquet but I don't want to add red-parquet dependency to red-datasets for easy to install. red-parquet is an extension library. So it's difficult to install rather than a pure Ruby library.

Solution candidates:

• Split red-datasets to red-datasets-parquet or something (like red-datasets-arrow)
• Use soft dependency like activerecord
  • Users need to install red-parquet explicitly if they want to use Apache Parquet based dataset
• ...

[kou]

Close in favor of https://github.com/red-data-tools/red-datasets-parquet/issues/1 .