Hi, I'm working on a script using SQLAlchemy against a PostgreSQL database and using Python's multiprocessing. The pattern is for each thread to:
- start a transaction (session.begin()) - retrieve the "next row in table X that has not yet been processed" - set a "being_processed" flag in the row so no other query will return it - close the transaction (session.commit()) The rest of the thread then performs the work, saves the results back, and cleans up. This is all working well except for one thing - multiple threads are retrieving the same row. My first solution was to pull the work above into the main thread, but this won't work as I'd like to run this same script on *multiple* machines - the database needs to be the gatekeeper. Does anyone have any suggestions on how I can make a database-wide exclusive transaction through SQLAlchemy (or otherwise!)? I'm using SQLAlchemy 0.6.7. Cheers, Demitri -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
