On Wed, July 11, 2007 01:41, Fei Liu wrote: > I just realized my problem was using transactor model within a > multi-thread environment...Is there any tutorial or example code using > pqxx in a multi-thread application environment? Thanks
Not yet, and we still need to do a lot of work to include locks. Right now libpqxx itself doesn't do any locking. There are several ways to ensure thread safety for your use of libpqxx: 1. Do all your database work in a single thread. It saves time on establishing multiple connections, too. 2. Give each thread its own connection, and don't interchange libpqxx objects between threads. This may scale better or worse than using a single thread, depending on the job. 3. Lock whenever you access any libpqxx object that may also be accessed by other threads. Think of each connection as a separate world, and all objects related to that connection are part of that world. Whenever multiple threads can step into the same world at the same time, acquire a lock that you associate with that world. The last option is the most flexible, but that also means it's dangerous. For example, you must make sure that you don't try to open a transaction on a connection while another thread still has a transaction open on the same connection. I would use option 3 only for connection pooling. Jeroen _______________________________________________ Libpqxx-general mailing list Libpqxx-general@gborg.postgresql.org http://gborg.postgresql.org/mailman/listinfo/libpqxx-general
