CHECKSUM Integrity Checking and Physical Database Integrity
Unfortunately, not all hardware devices have end‑to‑end error detection and correction schemes in place, and it is possible for corrupted data to be written to the database. To minimize this problem, Teradata Database provides a mechanism for DBAs to selectively enforce physical data integrity at the level of disk I/O. When implemented, the feature checksums everything from system memory to disk, thus enforcing true end‑to‑end data integrity checking (see “Disk I/O Integrity Checking” on page 666 and “Integrity Checking Using a Checksum” on page 668).
You can specify various levels of corruption detection rigor by selecting among mechanisms that use various degrees of sampled checksums, including full checksums, to detect disk I/O corruption. Teradata Database controls the levels of physical integrity enforcement in two complimentary ways: