Define reconciliation rules and criteria (record counts, field-level comparison, etc.).
Identify any specific business rules to validate during reconciliation.
Create a data mapping document to understand the relationship between the old and new system data structures.
2. Conduct Initial Full Migration :
Perform a full data migration from the source to the target system.
3. Reconciliation Process :
Count records in both systems and compare.
Perform field-level comparisons using automated tools.
Check for aggregated data consistency (totals, averages).
Ensure referential integrity by checking relationships between records.
Validate that business rules and data constraints are respected.
4. Resolve Discrepancies :
If discrepancies are found, identify the cause (e.g., mapping errors, transformation issues).
Make corrections and re-run reconciliation until the data matches.
5. Post-Migration Monitoring :
After initial reconciliation, monitor ongoing data consistency between systems, especially if the migration involves real-time sync or delta migration.
