SQLite3 and Multiprocessing

Question

I noticed that sqlite3 isn´t really capable nor reliable when i use it inside a multiprocessing enviroment. Each process tries to write some data into the same database, so

Answer 1

If I had to build a system like the one you describe, using SQLITE, then I would start by writing an async server (using the asynchat module) to handle all of the SQLITE database access, and then I would write the other processes to use that server. When there is only one process accessing the db file directly, it can enforce a strict sequence of queries so that there is no danger of two processes stepping on each others toes. It is also faster than continually opening and closing the db.

In fact, I would also try to avoid maintaining sessions, in other words, I would try to write all the other processes so that every database transaction is independent. At minimum this would mean allowing a transaction to contain a list of SQL statements, not just one, and it might even require some if then capability so that you could SELECT a record, check that a field is equal to X, and only then, UPDATE that field. If your existing app is closing the database after every transaction, then you don't need to worry about sessions.

You might be able to use something like nosqlite http://code.google.com/p/nosqlite/