Once the coding issues are resolved, you can check the state of health of your system with "health check reports".
The Health check report targets problems that are not expected to happen. When e.g. the Business defined a document should be in a status "To be approved", "Released" or "Rejected", the report would list documents in a status other than these. If the 3 statuses from this example are expected to cover all documents - other statuses may go unnoticed, causing data integrity which looks very innocent.
Health check reports are much easier to build and run (as part of a daily or weekly system checklist) than it is to prevent problems from arising. Let it go wrong but make sure it doesn't go unnoticed. Report on anything that is not flying the way it's designed to fly.
As the Health check report sounds nice in theory, it's quite a challenge to report on anything that could ever go wrong - so choose your health check target carefully. There's more information on health check reports in the AbapcadabrA issue about "Blue prints".