adbc

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# ADBC PostgreSQL Driver

This implements an ADBC driver that wraps [libpq][libpq], the client
library for PostgreSQL.  This is still a work in progress.

This project owes credit to 0x0L's [pgeon][pgeon] for the overall
approach.

**NOTE:** this project is not affiliated with PostgreSQL in any way.

[libpq]: https://www.postgresql.org/docs/current/libpq.html
[pgeon]: https://github.com/0x0L/pgeon

## Building

Dependencies: libpq itself. This can be installed with your favorite
package manager; however, you may need to set the `PKG_CONFIG_PATH`
environment variable such that `pkg-config` can find libpq.

See [CONTRIBUTING.md](../../CONTRIBUTING.md) for details.

## 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
```

Alternatively use the `docker compose` provided by ADBC to manage the test
database container.

```shell
$ docker compose up postgres-test
# When finished:
# docker compose down postgres-test
```

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
$ ctest
```

Users of VSCode can use the CMake extension with the supplied CMakeUserPresets.json
example to supply the required CMake and environment variables required to build and
run tests.