Teradata VS monitors the frequency of data access at the cylinder level, and periodically migrates cylinders that store more frequently accessed (hotter) data to faster storage media, and less frequently accessed (colder) data to slower storage media. The monitoring process requires some time to gauge the frequency of access before data can be migrated to appropriate media.
The temperature that is assigned to new data, before it has been migrated for the first time, is normally determined by defaults set in the DBS Control utility. This chapter discusses techniques for explicitly specifying data temperatures, which can precede or override the normal monitoring and migration process.
For more information on the benefits and considerations of specifying and changing data temperatures, see Chapter 1: “Overview.”