[DataMapper] Re: thread safety vs. Sqlite3Error: database is locked

[Earle Clubb]

Dirkjan Bussink wrote: On Thu, Nov 6, 2008 at 11:17 PM, Earle Clubb <[EMAIL PROTECTED]> wrote: sqlite3 can only handle one write at a time. It raises the locked exception when another thread or process has an exclusive lock on the db. I got around this by putting a wrapper around the lowest-level query methods which will retry up to 4 times before passing the exception up the stack. Here's my code, which I placed in the same file as my model definitions: Well, trying again is not guaranteed to be safe in all conditions. The only way to properly handle this is using a Mutex object to guarantee that only one query accesses sqlite3 at the same time. This probably should be handled at the do_sqlite3 level. To the original poster, if you really want queries to be run in parallel, you should use a full fledged RDMS like PostgreSQL or MySQL. You're right that it's not guaranteed to be safe, but I think it's the best you can do with sqlite3.  Using a mutex would help within the same process (and maybe between ruby processes), but I don't see a way to do that between say, ruby, php, and c processes. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "DataMapper" group. To post to this group, send email to datamapper@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/datamapper?hl=en -~----------~----~----~----~------~----~------~--~---