Whether you are replacing the old legacy system, or upgrading from the previous version, the business will need legacy data to be migrated to the new system. Data migration testing is basically testing the data integrity and data quality. No matter how you decided to migrate the data, the testing team needs to analyze the migrated data, and then perform validation and transactions at the end of the data migration to ensure that the migrated data is complete and accurate, in order to carry out future transactions. For example, if open sales orders are migrated from the legacy system, you need to ensure that you are able to ship and invoice these orders and ultimately, collect the cash.

You also need to ensure that numbers such as order count, account balance, and inventory levels match between the legacy system and new system in order to make the migration complete and accurate. A solid data migration strategy should also define the parameters for the success of data migration testing.