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# Overview

## What is this?

Apache Arrow Flight SQL adapter for PostgreSQL is a PostgreSQL
extension that adds an [Apache Arrow Flight
SQL][apache-arrow-flight-sql] endpoint to PostgreSQL.

Apache Arrow Flight SQL is a protocol to use [Apache Arrow
format][apache-arrow-format] to interact with SQL databases. You can
use Apache Arrow Flight SQL instead of [the PostgreSQL wire
protocol][postgresql-protocol] to interact with PostgreSQL by Apache
Arrow Flight SQL adapter for PostgreSQL.

Apache Arrow format is designed for fast typed table data exchange. If
you want to get large data by `SELECT` or `INSERT`/`UPDATE` large
data, Apache Arrow Flight SQL will be faster than the PostgreSQL wire
protocol.

## Benchmark

See also [a simple benchmark result][benchmark-integer] that just
executes `SELECT * FROM integer_only_table`. It shows that Apache
Arrow Flight SQL is faster than the PostgreSQL wire protocol when
result data is large.

[apache-arrow-flight-sql]: https://arrow.apache.org/docs/format/FlightSql.html
[apache-arrow-format]: https://arrow.apache.org/docs/format/Columnar.html
[postgresql-protocol]: https://www.postgresql.org/docs/current/protocol.html
[benchmark-integer]: https://github.com/apache/arrow-flight-sql-postgresql/tree/main/benchmark/integer