Data migration
Post-migration: After data migration, results are subjected to data verification to determine whether data was accurately translated, is complete, and supports processes in the new system. During verification, there may be a need for a parallel run of both systems to identify areas of disparity and forestall erroneous data loss. Additional documentation and reporting of the migration project is conducted, and once the migration is validated complete, legacy systems may also be decommissioned. Migration close-out meetings will officially end the migration process.
Web2py
web2py supports database migrations—change the definition of a table and web2py ALTERs the table accordingly. Migrations are automatic, but can be disabled for any table, and migration is typically disabled when an application is ready for live distribution. Migrations and migration attempts are logged, documenting the changes.