========================
Setting up your database
========================

Mailman uses the SQLAlchemy_ ORM to provide persistence of data in a
relational database.  By default, Mailman uses Python's built-in SQLite3_
database, however, SQLAlchemy is compatible with PostgreSQL_ and MySQL, among
possibly others.

Currently, Mailman is known to work with either the default SQLite3 database,
or PostgreSQL.  (Volunteers to port it to other databases are welcome!).  If
you want to use SQLite3, you generally don't need to change anything, but if
you want Mailman to use PostgreSQL, you'll need to set that up first, and then
change a configuration variable in your ``/etc/mailman.cfg`` file.

Two configuration variables control which database Mailman uses.  The first
names the class implementing the database interface.  The second names the URL
for connecting to the database.  Both variables live in the ``[database]``
section of the configuration file.


SQLite3
=======

As mentioned, if you want to use SQLite3 in the default configuration, you
generally don't need to change anything.  However, if you want to change where
the SQLite3 database is stored, you can change the ``url`` variable in the
``[database]`` section.  By default, the database is stored in the *data
directory* in the ``mailman.db`` file.  Here's how you'd force Mailman to
store its database in ``/var/lib/mailman/sqlite.db`` file::

    [database]
    url: sqlite:////var/lib/mailman/sqlite.db


PostgreSQL
==========

First, you need to configure PostgreSQL itself.  This `Ubuntu article`_ may
help.  Let's say you create the `mailman` database in PostgreSQL via::

    $ sudo -u postgres createdb -O $USER mailman

You would then need to set both the `class` and `url` variables in
`mailman.cfg` like so::

    [database]
    class: mailman.database.postgresql.PostgreSQLDatabase
    url: postgres://myuser:mypassword@mypghost/mailman

That should be it.

If you have any problems, you may need to delete the database and re-create
it::

    $ sudo -u postgres dropdb mailman
    $ sudo -u postgres createdb -O myuser mailman

My thanks to Stephen A. Goss for his contribution of PostgreSQL support.


.. _SQLAlchemy: http://www.sqlalchemy.org/
.. _SQLite3: http://docs.python.org/library/sqlite3.html
.. _PostgreSQL: http://www.postgresql.org/
.. _MySQL: http://dev.mysql.com/
.. _`Ubuntu article`: https://help.ubuntu.com/community/PostgreSQL