The Perl DBI interface to Postgresql, module DBD::Pg, has a ping() method that is suppose to determine if a database connection is alive. It can be seen here (see: dbd_db_ping): http://search.cpan.org/src/DBDPG/DBD-Pg-1.43/dbdimp.c It pings by calling: status = _result(imp_dbh, "SELECT 'DBD::Pg ping test'"); This fails when a transaction fails -- for example when doing a serialized transaction and another session preforms an update between the serialized transaction's SELECT and UPDATE. In this situation no SELECTS are allowed until a ROLLBACK. In Perl, this failure of Ping results in a new database connection being created, even though the connection is still valid. I'm about to post a bug report on DBD::Pg, but I'm wondering if anyone here could suggest a better way to implement ping() that doesn't fail just because Postgresql is not allowing SELECTS. What I did in my code was if ping fails, call rollback and then try ping one more time. But, I'm not clear if that works in a more general case or what might happen if the connection really is broken. -- Bill Moseley moseley@xxxxxxxx ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
