John Nagle wrote: > pyt...@bdurham.com wrote: >> I'm looking for the best practice way for a multi-threaded python web >> server application to read/write to a shared file or a SQLite database. >> >> What do I need to do (if anything) to make sure my writes to a regular >> file on disk or to a SQLite database are atomic in nature when multiple >> clients post data to my application simultaneously? > > SQLite can do that correctly, but SQLite isn't intended for use > as a database engine for a busy database being used by many > concurrent operations. Especially if those operations involve > updates. Any update in SQLite locks all tables involved for the duration > of the operation. When SQLite hits a lock, it returns an error code, and > the caller should retry after a delay. If this occurs frequently in > your application, you've hit the limits of SQLite. Then it's > time to move up to MySQL. > Or PostgreSQL, which has superior SQL standards conformance and excellent high-volume data performance.
> If you have enough traffic that you need a multi-threaded web server, > it's probably time to move up. > Yes, but not to MySQL, please. Particularly since there is a sword of Damocles hanging over its head while the Oracle takeover of Sun is pending. regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 PyCon is coming! Atlanta, Feb 2010 http://us.pycon.org/ Holden Web LLC http://www.holdenweb.com/ UPCOMING EVENTS: http://holdenweb.eventbrite.com/ -- http://mail.python.org/mailman/listinfo/python-list
