When upgrading, changes should be kept to a minimum. It is not sensible to include new application functionality into the upgrade cycle because this making comparing previous results with current results more difficult.

Changes should only be made where there are compatibility issues between versions of Ingres. Make the changes in the development environment, and then test according to the test plan. When testing, use data volumes and distributions that are as similar to the live data as possible.

Do not just test applications merely for data validity; also perform concurrency tests, load and volume testing, and housekeeping tests.