Record counts are only the first check
A migration can copy every row and still lose the business meaning of the data. A subscription linked to the wrong account or an offer mapped to the wrong version may be structurally valid while producing an incorrect customer outcome.
Define reconciliation rules around relationships as well as individual fields. Use real business questions: can the correct customer see the subscription, and does an amendment refer to the conditions that were actually accepted?
Plan for changes during the move
Customer and order activity does not necessarily stop while a migration runs. The plan needs a baseline, a strategy for changes made after that baseline and an agreed point at which the target becomes authoritative.
An update timestamp alone may not resolve conflicting changes. Document the ownership rule for each shared field and the process for reviewing records that do not reconcile automatically.
Make cutover a controlled decision
Rehearse the transfer with representative data and verify the workflows that depend on it. Access rights, external references and pending orders deserve specific attention because they can be missed by a field-level comparison.
Set acceptance criteria before the final migration and identify the person or team responsible for each unresolved category. A rollback plan should also explain what happens to changes created after the target begins accepting work.
- Check customer-to-account and subscription relationships.
- Reconcile product identifiers and effective versions.
- Track pending orders through the transition.
- Define ownership, acceptance criteria and recovery steps.