docs/source/python/driver_manager.rst

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.. py:currentmodule:: adbc_driver_manager

==============
Driver Manager
==============

The ``adbc_driver_manager`` package provides a :term:`driver manager` interface
for Python. The package provides two APIs:

1. Low-level bindings that are essentially the same as the :doc:`C API <../format/specification>`.
2. If PyArrow or Polars are installed, a DBAPI_ (PEP 249) compliant interface.

.. _DBAPI: https://peps.python.org/pep-0249/

Installation
============

.. code-block:: shell

   pip install adbc_driver_manager

Usage
=====

The driver manager is different from the individual, driver-specific packages
such as ``adbc_driver_postgresql``.

With the driver-specific packages, you connect to the target database with the
``connect`` method provided by the package you're using.  For example,
:func:`adbc_driver_postgresql.connect` or :func:`adbc_driver_sqlite.connect`.
The driver shared library is bundled with the respective package and loaded
invisibly for the user.

With the driver manager package, you use a single package and API regardless of
the database you're connecting to. However, the user must install the driver for
their database as a separate step. :term:`Driver manifests <driver manifest>`
are a first step in making this experience better for users but more work is
planned to make this as straightforward as using driver-specific packages.

Low-Level API
-------------

First, create an :py:class:`AdbcDatabase`, passing ``driver`` and (optionally)
``entrypoint``. Then, create an :py:class:`AdbcConnection`.

.. note:: See :doc:`../format/driver_manifests` for more information on what to pass as the ``driver`` argument and how the driver manager finds and loads drivers.

.. code-block:: python

   import adbc_driver_manager

   # Note: You must install the driver shared library (.so, .dylib, .dll)
   # separately
   with adbc_driver_manager.AdbcDatabase(driver="PATH/TO/libadbc_driver_sqlite.so") as db:
       with adbc_driver_manager.AdbcConnection(db) as conn:
           pass

Connecting to a second database could be done in the same session using the same
code just with a different ``driver`` argument.

DBAPI API
---------

Use the DBAPI_ API by calling the ``dbapi.connect`` method, passing ``driver``
and (optionally) ``entrypoint``. These arguments work the same as with the
low-level API.

.. code-block:: python

   from adbc_driver_manager import dbapi

   # Note: You must install the driver shared library (.so, .dylib, .dll)
   # separately
   with dbapi.connect(driver="PATH/TO/libadbc_driver_sqlite.so") as conn:
      pass


API Reference
=============

See the API reference: :doc:`./api/adbc_driver_manager`.