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# Red Parquet - Apache Parquet Ruby

Red Parquet is the Ruby bindings of Apache Parquet. Red Parquet is based on GObject Introspection.

[Apache Parquet](https://parquet.apache.org/) is a columnar storage format.

[GObject Introspection](https://wiki.gnome.org/action/show/Projects/GObjectIntrospection) is a middleware for language bindings of C library. GObject Introspection can generate language bindings automatically at runtime.

Red Parquet uses [Apache Parquet GLib](https://github.com/apache/arrow/tree/master/c_glib/parquet-glib) and [gobject-introspection gem](https://rubygems.org/gems/gobject-introspection) to generate Ruby bindings of Apache Parquet.

Apache Parquet GLib is a C wrapper for [Apache Parquet C++](https://github.com/apache/arrow/tree/master/cpp/src/parquet). GObject Introspection can't use Apache Parquet C++ directly. Apache Parquet GLib is a bridge between Apache Parquet C++ and GObject Introspection.

gobject-introspection gem is a Ruby bindings of GObject Introspection. Red Parquet uses GObject Introspection via gobject-introspection gem.

## Install

Install Apache Parquet GLib before install Red Parquet. See [Apache Arrow install document](https://arrow.apache.org/install/) for details.

Install Red Parquet after you install Apache Parquet GLib:

```text
% gem install red-parquet
```

## Usage

```ruby
require "parquet"

table = Arrow::Table.load("/dev/shm/data.parquet")
# Process data in table
table.save("/dev/shm/data-processed.parquet")
```