17.10 - USI and NUSI Properties - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Fundamentals

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1141-171K
Language
English (United States)
USI NUSI
  • Guarantee that each complete index value is unique.
  • Any access using the index is a two-AMP operation.
  • Useful for locating rows having a specific value in the index.
  • Can be hash-ordered or value-ordered.

    Value-ordered NUSIs are particularly useful for enhancing the performance of range queries.

  • Can include covering columns.
  • Any access using the index is an all-AMP operation.