Database SYSUDTLIB is linked with database DBC and is only restored if DBC is restored. SYSUDTLIB cannot be specified as an individual object in a RESTORE statement.
If database DBC is involved in a restore operation, it is always restored first, followed by database SYSUDTLIB. If additional databases are being restored, they follow SYSUDTLIB in alphabetical order.
An all-AMPs restore or a specific AMP restore can use archive files created by any of the following:
- An all-AMPs archive
- A cluster archive
- A specific AMP archive
- An archive of selected partitions
During a restore of a Teradata Database, Teradata ARC issues messages in the following format as it restores different types of objects:
"UDFname" - n,nnn,nnn BYTES, n,nnn,nnn ROWS RESTORED "procedurename" - n,nnn,nnn BYTES, n,nnn,nnn ROWS RESTORED "macroname" - MACRO RESTORED "methodname" - METHOD RESTORED "methodname" - n,nnn,nnn BYTES, n,nnn,nnn ROWS RESTORED "tablename" - n,nnn,nnn BYTES, n,nnn,nnn ROWS RESTORED "triggername" - TRIGGER RESTORED "UDTname" - TYPE RESTORED "viewname" - VIEW RESTORED
When all tables are restored, Teradata ARC issues this message:
STATEMENT COMPLETED
At the start of a restore, or after a system restart, all offline AMPs are listed in the output log.
After each restore, compare the contents of the output log with listings of tables that were restored to determine which tables were not restored to offline AMPs.
Teradata ARC supports duplicate rows in a restore operation. However, if a restart occurs during the restore of a table with duplicate rows, the duplicate rows involved in the restart might be removed.
When a database or table restores from an older version source system with a different configuration, it affects the time and space required to restore data to the destination system. The data must be redistributed among the new set of AMPs. The system uses a different algorithm to copy and restore when the number of AMPs is different between the source and destination systems. This new algorithm is usually faster when the configurations are different. The old algorithm may be faster in some restricted situations.
Unique secondary indexes are distributed across all AMPs. Therefore, RESTORE does not rebuild unique secondary indexes, even if the indexes are in a cluster that is not being restored. Use the BUILD statement to build and revalidate unique indexes.