On Oct 31, 2011, at 8:45 AM, Benjamin Sims wrote: > Hi all, > > I'm seeing this error intermittently in my application since switching to > MySQL - it occurs on several different pages and I can't track down why: > > StatementError: Can't reconnect until invalid transaction is rolled back > (original cause: InvalidRequestError: Can't reconnect until invalid > transaction is rolled back) 'SELECT [... the same select every time, which > gets a user from the database]
how are you handling threading, as well as Session lifecycle ? this kind of error usually occurs from one of two things: a. sharing Sessions, or objects attached to them, between threads or b. no clear point of Session start/end, incorrect handling of exceptions, etc. > > I have searched on the error and read the various discussions, for example > this one: > > http://groups.google.com/group/sqlalchemy/browse_thread/thread/a8031eefc4d5d0cd > > My understanding is that somewhere in my code I need to be ensuring that I do > rollback/commit/close when the operation is complete. The problem is... > where? Is there a way I can get a log to see the original query/point in my > code which triggers the error. sure you should turn on SQLAlchemy logging fully (http://www.sqlalchemy.org/docs/core/engines.html?highlight=logging#configuring-logging) , and also make sure you aren't squashing exceptions (i.e. except MyException, e: pass type of thing) - also you'd want to add code such as log.error("exception occurred", exc_info=True) to the point at which exceptions are caught so that a full stack trace is written out to the log. -- 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.
