Databases and Persistence

Another Python SQLite Wrapper
APSW is a thin wrapper over the SQLite 3 API. [Open Source, zlib/libpng license]
http://code.google.com/p/apsw/

DMtools
A data mining toolbox with caching of database queries and parallelism within a collection of independent queries. [Open Source, GPL]
http://datamining.anu.edu.au/software/dmtools/

MetaKit for Python
A Python interface to MetaKit. MetaKit is an embeddable database which runs on Unix, Windows, Macintosh, and other platforms. [Open-Source, MIT]
http://www.equi4.com/metakit/python.html

Metakit for Python (Mk4py)
A lower-level API for the Metakit C++ core extension, and uses SCXX by Gordon McMillan as C++ glue interface. [X/MIT-style and commercial licenses]
http://www.equi4.com/metakit/

mxBeeBase
On-disk B+Tree Based Database Kit. [Open Source]
http://www.egenix.com/products/python/mxBase/mxBeeBase/

PDO
Python Database Objects provides a convenient Object Oriented API for database access in Python. PDO supports multiple RDBMS with the same API, and provides features not found in the DB-API spec, such as column access by name. [OPen source, BSD style license]
http://pdo.neurokode.com/

pSQL
A wrapper above MySQLdb which renders MySQL databases as very comfortable pythonic objects.
http://software.fionet.com/pSQL/

pyBSDdb
Python bindings for BerkeleyDB 3.x embeddable database. [Open Source, BSD-like]
http://pybsddb.sourceforge.net/

PyDO2
An ORM (Object-Relational Mapper) database access library for Python. [Open Source, GPL]
http://skunkweb.sourceforge.net/pydo2.html

Python Database Row Module
This Python 2.2 module defines light-weight objects which allow very flexible access to a fixed number of positional and named attributes via several interfaces. [Open Source, BSD-like]
http://opensource.theopalgroup.com/

Python SQL Database Access System
A simple and consistent programming interface to SQL databases, in Python. [Open source, Python Software Foundation License]
http://sourceforge.net/projects/pysqldb/

SnakeDb
An easy database API that is a wrapper around other Python database modules (like Gadfly and MySQLdb). [Open source, GPL]
http://sourceforge.net/projects/snakedb/

SQLAlchemy
SQL toolkit and Object Relational Mapper that gives application developers the full power and flexibility of SQL. [Open Source, MIT license]
http://www.sqlalchemy.org/

SQLObject
An Object Relational Manager for providing an object interface to your database, with tables as classes, rows as instances, and columns as attributes. [Open Source, LGPL]
http://www.sqlobject.org/

ZODB
The Z Object Database, or the ZODB for short, is a powerful and easy-to-use object persistence system for Python. [Open Source, ZPL]
http://wiki.zope.org/ZODB/FrontPage

ZODB-Tutorial.py
A number of hands-on code example how to use the ZODB.
http://www.h7.dion.ne.jp/~harm/ZODB-Tutorial.py