17.10 - Queries Using a Hash Index - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Fundamentals

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1141-171K
Language
English (United States)

In most respects, a hash index is similar to a base table. For example, you can perform COLLECT STATISTICS, DROP STATISTICS, HELP, and SHOW statements on a hash index.

Unlike base tables, you cannot do the following things with hash indexes:

  • Query or update hash index rows explicitly.
  • Store and maintain arbitrary query results such as expressions.
  • Create explicit unique indexes on its columns.
  • Partition the primary index of the hash index.