How To Conduct Effective Software Testing When Migrating Data

In software testing, data migration testing is conducted to compare migrated data with original data to discover any discrepancies when moving data from a legacy databases to a new destination. As organizations move their operations to the cloud—one of the foundational pillars of digital transformation— data migration testing ensures the integrity of the mission-critical systems and business as usual for business users.

Data can be migrated automatically through a migration tool or by manually extracting data from the source database and inserting the data into the destination database.

Data migration testing encompasses data–level validation testing and application-level validation testing.

Data-level validation testing verifies that data has been migrated from multiple databases to a common database without any discrepancies. During data level validation testing, data will be verified at three levels.

In application-level validation testing, a software tester verifies the functionality of a sample migration application that was migrated from an old legacy system to the new system. Application-level validation testing ensures smooth running of the migrated application with the new database using following validations:

• After migration, log in to the new application and verify a sample data set.
• After migration, log in to legacy systems and verify the locked/unlocked status of accounts.
• Verify customer support access to all legacy systems, despite the user being blocked during the migration process.
• Verify whether new users are prohibited from creating a new account in a legacy system after launching the new application.
• Verify immediate reinstatement of user access to the legacy system if migration to the new system fails.
• Verify the termination of access to legacy systems at migration.
• Validate system login credentials for the new application.

When you test database migration, it is important to create a set of SQL queries to validate the data before (source database) and after (destination database) migration. The validation queries can be arranged in a hierarchy and it should cover the designed scope.

For example, to test if all users have been migrated, it is essential to check how many users are in the source database and how many have been migrated. Checking the raw counts of each database will ensure this.
Take a sample data set from the source and compare the data with the destination data in the database. Testing tips:

• Always take the most important dataset and data that have values in all columns
• Verify the data types after the migration
• Check the different time formats/zones, currencies etc.
• Check for data with special characters
• Find data that should not be migrated
• Check for duplicated data after migration

A sample test case can be created as shown below: