Restoring a Table with Fallback
If a data table with fallback from an all-AMPs data tables or cluster archive is restored while one or more AMPs are offline, Teradata ARC generates the information to restore the data on the offline AMPs when they return to operation. The system recovery process restores the offline AMPs when they return to online status.
Restoring a Table Without Fallback
If a data table without fallback (or from a specific-AMP archive) is restored while one or more AMPs that must also be restored are offline, restore the data table to each of the offline AMPs as soon as the AMPs come back online.
The exclusive utility lock is automatically placed on the data table for the all-AMPs restore and on each offline processor when the AMPs return to an online status. The lock allows Teradata Archive/Recovery Utility to finish the restoring process before the table can be accessed.
Unique Secondary Indexes
If a table without fallback is restored with AMPs offline, unique secondary indexes defined for the table are invalidated. This prevents future updates to the table until the unique secondary indexes are regenerated. Drop and recreate them or use the BUILD statement.
Restoring Change Images
The Teradata Database always restores change images to the AMP that contains the data row, unless the row is from a single after-image journal. If a journal table contains change images for data tables with fallback, the database automatically creates the change images necessary for the offline AMPs when a recovery operation uses the restored journal.
If the journal table contains change images for tables without the fallback option, repeat the journal table restore for any offline AMPs when they return to online status. Any recovery activity using the restored journal must be repeated when the AMPs return to online status.