16.20 - USI and NUSI Properties - Teradata Database - Teradata Vantage NewSQL Engine

Teradata Vantageâ„¢ SQL Fundamentals

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Published
March 2019
Language
English (United States)
Last Update
2019-05-02
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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.