17.10 - Unique and Nonunique Primary Index Considerations - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Fundamentals

Advanced SQL Engine
Teradata Database
Release Number
Release Date
July 2021
Content Type
Programming Reference
Publication ID
English (United States)

In addition to uniform distribution of data and optimal access considerations, other guidelines and performance considerations apply to selecting a unique or a nonunique column set as the primary index for a table.

Other considerations can include:

  • Primary and other alternate key column sets
  • The value range seen when using predicates in a WHERE clause
  • Whether access can involve multiple rows or a spool file or both