Typically though, restoring from backup is a dicey proposition. If a schema migration causes issues down the line, you're likely to have production data that ne

Typically though, restoring from backup is a dicey proposition. If a schema migration causes issues down the line, you're likely to have production data that needs to be kept. E.g. a room reservation system can't just drop two days of bookings on the floor because some financial accounting table was improperly migrated. Partial restores are also difficult if you've drunk deep from the relational chalice. On the other hand, if the upgrade was broken, it's unlikely the downgrade will work. The situation where the downgrade works is when you don't need it. On the database i work on we fix bad upgrades that weren't discovered immediately by layering another upgrade over it.