After talking to some coworkers who have more database experience than I do, they thought the issue might be that I'm connecting/disconnecting to the DB too often (I'm attempting to get in touch with our Oracle DBA team to ask them as well).
This is hilarious -- it anthropomorphizes the database into a being that will get frustrated with your rapid connection/disconnection behaviour, and stop answering. I'm pretty sure there's no database setting that limits the number of connections made in a time period. :)
Alex / talexb / Toronto
Thanks PJ. We owe you so much. Groklaw -- RIP -- 2003 to 2013.