Embodiments described herein relate to an improved technique for maintaining a consistent state during data migration operations in an active database system. Data can be copied from database table(s) of the active database system into a corresponding database table(s) in the shadow system. Snapshots of the active system can be taken at a specified point in time and used to establish a point of consistency. Later, the snapshot data can be compared with the data in the shadow database system. If the data matches, then the active and shadow database systems are at a consistent state and the data migration process completes. If the data does not match, embodiments are configured to restore the consistent state at the specified point in time by copying the snapshot data into the shadow database table(s).