The key question
A packaged application, a PL/SQL-heavy custom system and an archive database can have completely different constraints. A single migration mandate can hide those differences.
What to inventory
- Map databases to applications and business owners.
- Capture how much application code can change and any vendor certification constraints.
- Document lifecycle, dependencies and operational effort.
Design the target deliberately
Create explicit groups: stabilise first, simplify selectively, assess for an engine change, or retire in a controlled way. Sequence by business relevance, technical feasibility and available capacity. Decommissioning an obsolete system can create more value than an expensive port.
A concrete validation step
A one-page record per application should show objective, owner, changeability, critical dependencies and the next piece of evidence required. That makes portfolio decisions comparable.
Evidence required before sign-off
- Confirm priorities with business owners.
- Include shared data and interfaces.
- Check dependencies on upcoming application changes.
- Update decisions transparently as new evidence appears.
Primary sources & further reading
These recommendations are engineering guidance. Specific options depend on source and target versions, privileges and operating model.