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# Apache Arrow Flight

[![Crates.io](https://img.shields.io/crates/v/arrow-flight.svg)](https://crates.io/crates/arrow-flight)

See the [API documentation](https://docs.rs/arrow_flight/latest) for examples and the full API.

The API documentation for most recent, unreleased code is available [here](https://arrow.apache.org/rust/arrow_flight/index.html).

## Usage

Add this to your Cargo.toml:

```toml
[dependencies]
arrow-flight = "53.3.0"
```

Apache Arrow Flight is a gRPC based protocol for exchanging Arrow data between processes. See the blog post [Introducing Apache Arrow Flight: A Framework for Fast Data Transport](https://arrow.apache.org/blog/2019/10/13/introducing-arrow-flight/) for more information.

This crate provides a Rust implementation of the
[Flight.proto](../format/Flight.proto) gRPC protocol and
[examples](https://github.com/apache/arrow-rs/tree/master/arrow-flight/examples)
that demonstrate how to build a Flight server implemented with [tonic](https://docs.rs/crate/tonic/latest).

## Feature Flags

- `flight-sql-experimental`: Enables experimental support for
  [Apache Arrow FlightSQL], a protocol for interacting with SQL databases.

- `tls`: Enables `tls` on `tonic`

## CLI

This crates offers a basic [Apache Arrow FlightSQL] command line interface.

The client can be installed from the repository:

```console
$ cargo install --features=cli,flight-sql-experimental,tls --bin=flight_sql_client --path=. --locked
```

The client comes with extensive help text:

```console
$ flight_sql_client help
```

A query can be executed using:

```console
$ flight_sql_client --host example.com statement-query "SELECT 1;"
+----------+
| Int64(1) |
+----------+
| 1        |
+----------+
```

[apache arrow flightsql]: https://arrow.apache.org/docs/format/FlightSql.html