17.10 - Hash-Related Functions - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1145-171K
Language
English (United States)
Hash-related functions return information about the:
  • Primary or fallback AMP that corresponds to a given hash bucket number
  • Hash bucket number that corresponds to a given row hash value
  • Row hash value for the primary index of a row
  • Highest AMP number
  • Highest hash bucket number
  • Maximum value that can be generated by applying the hash function to an unsigned integer

Use the hash-related functions to identify the statistical properties of the current primary index or secondary index, or to evaluate these properties for other columns to determine their suitability as a future primary index or secondary index. The statistics can help you to minimize hash synonyms and enhance the uniformity of data distribution.