16.20 - Unique and Nonunique Primary Index Considerations - 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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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