ok, well the full run took 12 days with about 200,000 customer documents, so it wasn't one DBI call for 12 days - and it was a bug in the client data that triggerred it. We use Oracle, and as I said it was a first run, so while we fixed various issues and optimised our calls and code, we just let the test run continue for a benchmark. Some of the data sets are huge - before going live, we loaded >2Gb of historical data first. We now run our end-of-month prints in about 6 hours.