15.00 - NUSI Summary - Teradata Database

Teradata Database Design

Teradata Database
User Guide

NUSI Summary

  • 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.

  • Any access is an all-AMPs operation with the exception of the case where a NUSI is defined on the same column set as the primary index for the table.
  • If an index is defined with an ORDER BY clause, it counts as 2 consecutive indexes against the table limit of 32 secondary, hash, and join indexes (see “Importance of Consecutive Indexes for Value‑Ordered NUSIs” on page 485).
  • Related Topics

    For more information about secondary indexes., see SQL Data Definition Language under the topics CREATE INDEX and CREATE TABLE.