doc/source/overview.md

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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](https://arrow.apache.org/docs/format/FlightSql.html) endpoint to
PostgreSQL.

Apache Arrow Flight SQL is a protocol to use [Apache Arrow
format](https://arrow.apache.org/docs/format/Columnar.html) to
interact with SQL databases. You can use Apache Arrow Flight SQL
instead of [the PostgreSQL wire
protocol](https://www.postgresql.org/docs/current/protocol.html) 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.

[benchmark-integer]: https://github.com/apache/arrow-flight-sql-postgresql/tree/main/benchmark/integer