Selected partitions can be directly backed up and restored with a PARTITIONS WHERE option that restricts the list of rows processed. The PARTITIONS WHERE option operates on complete table partitions. A RESTORE (or COPY) operation wipes out selected partitions (specified by the PARTITIONS WHERE option) of an existing target table before recovering the rows stored on the backup tape. A backup operation on selected partitions is allowed with the same all-AMP BAR styles as for full tables.
Restoring selected partitions is affected by the maintenance activities that can occur on a table. For example, a user can add or delete a column, add or delete a secondary index, or change the partitioning expression.
If a selected partition was archived prior to one of these changes, restoring that partition back to the table might not be possible. Restoring selected partition data back to a table even if the target table has some characteristics that are different from the source stored on tape is allowed. However, not all changes are allowed and some will prevent the restoration of the selected partition data. For a list of acceptable and non-acceptable differences, see Changes Allowed to a PPI Table and Restrictions on Archiving Selected Partitions.
For an overview of backing up partitioned data with Teradata ARC, and the keywords for restoring partitioned data, see Archive Selected Partitions of PPI Tables.