python/adbc_driver_postgresql/README.md

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# ADBC PostgreSQL Driver for Python

This package contains bindings for the [PostgreSQL
driver](../../c/driver/postgresql/README.md), using the [driver
manager](../adbc_driver_manager/README.md) to provide a [DBAPI 2.0/PEP
249-compatible][dbapi] interface on top.

[dbapi]: https://peps.python.org/pep-0249/

## Building

Dependencies: a build of the PostgreSQL driver, and the
`adbc-driver-manager` Python package.  Optionally, install PyArrow to
use the DBAPI 2.0-compatible interface.

Set the environment variable `ADBC_POSTGRESQL_LIBRARY` to the path to
`libadbc_driver_postgresql.{dll,dylib,so}` before running `pip install`.

```
# If not already installed
pip install -e ../adbc_driver_manager

export ADBC_POSTGRESQL_LIBRARY=/path/to/libadbc_driver_postgresql.so
pip install -e --no-deps .
```

See [CONTRIBUTING.md](../../CONTRIBUTING.md) for details on the
general build process.

## Testing

A running instance of PostgreSQL is required.  For example, using Docker:

```shell
$ docker run -it --rm \
    -e POSTGRES_PASSWORD=password \
    -e POSTGRES_DB=tempdb \
    -p 5432:5432 \
    postgres
```

Then, to run the tests, set the environment variable specifying the
PostgreSQL URI before running tests:

```shell
$ export ADBC_POSTGRESQL_TEST_URI=postgresql://localhost:5432/postgres?user=postgres&password=password
$ pytest -vvx
```

See [CONTRIBUTING.md](../../CONTRIBUTING.md) for details on the
general test process.