Target tables can be either fallback or nonfallback.
The following table lists the differences between, and characteristics of, these tables.
|Fallback Tables||Nonfallback Tables|
|Teradata TPump task continues to execute even if AMPs are down, as long as there is not more than one AMP down, either logically or physically in a cluster.||If one or more AMPs are down prior to entering the task and if one or more target tables are nonfallback, Teradata TPump terminates.|
|If two or more AMPs in a cluster are logically or physically down, or both, the task does not run, or terminates if running.||The Teradata TPump task may be restarted as soon as all AMPs are back up.|
|During the task, if AMPs are down to the extent that data on the disk is corrupted, the affected tables must be restored.||If an AMP goes down once the task has started, the task cannot be restarted until all AMPs are back up.|
|Not applicable.||If more than one AMP in the same cluster is down, the database cannot come up.|
|Not applicable.||Certain I/O errors during the task corrupt the target table so that it must be restored. In this case, Teradata TPump terminates.|