Persistent dict in Python, backed up by sqlite3 and pickle, multithread-safe.
Project description
A lightweight wrapper around Python’s sqlite3 database, with a dict-like interface and multi-thread access support:
>>> mydict = SqliteDict('some.db') # the mapping will be persisted to file some.db >>> mydict['some_key'] = any_picklable_object >>> print mydict['some_key'] >>> print len(mydict) # etc... all standard dict functions work
Pickle is used internally to serialize the values. Keys are strings.
Features
Values can be any picklable objects (uses cPickle with the highest protocol).
Support for multiple tables (=dicts) living in the same database file.
Support for access from multiple threads (needed by e.g. Pyro). Vanilla sqlite3 gives you ProgrammingError: SQLite objects created in a thread can only be used in that same thread.
Concurrent requests are still serialized internally, so this “multithreaded support” doesn’t give you any performance benefit. It is a work-around for sqlite limitations in Python.
Installation
The module has no dependencies beyond 2.5 <= Python < 3.0. Install with:
sudo easy_install sqlitedict
or from the source tar.gz
python sqlitedict.py # run some tests sudo python setup.py install
Documentation
Standard Python document strings are inside the module:
>>> import sqlitedict >>> help(sqlitedict)
Comments, bug reports
sqlitedict resides on github. You can file issues or pull requests there.
sqlitedict is released as public domain, you may do with it as you please. Hack away.
Copyright (c) 2011 Radim Rehurek