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

SQL Fundamentals

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
17.00
Published
June 2020
Language
English (United States)
Last Update
2021-01-24
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B035-1141
lifecycle
previous
Product Category
Teradata Vantageâ„¢

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