Verifiable bulk changes

Operations that span many interdependent objects need more than a program that completes without errors.

A success message does not prove that the expected change actually happened. A further challenge is partial execution in systems that provide no transaction across the whole change.

I developed an approach based on four principles:

• Scope and dependencies — establishing which objects are to be changed and which relationships must be preserved.
• A verifiable plan — preparing the expected outcome and checking the plan against the current state before any modification starts.
• Controlled execution — allowing for partial execution and interruption, and making intermediate states recognisable.
• Independent verification — reading the state again after the operation and comparing it with the plan, rather than relying on the success message alone.

I designed and deployed a mechanism for planning, controlled execution and verification of bulk changes.

The solution distinguishes correct execution, partial change and situations in which the outcome cannot be confirmed unambiguously.

The mechanism passed 167 automated tests and successfully modified and verified more than 50,000 related objects in the pre-production environment. The solution was subsequently deployed to production.

Value: decisions based on the actual state of the system rather than on the reported execution status.