16.10 - Choosing a Software-based Compression Scheme - Teradata Database

Teradata Database Design

Product
Teradata Database
Release Number
16.10
Release Date
June 2017
Content Type
User Guide
Publication ID
B035-1094-161K
Language
English (United States)

In some cases, such as when column values are mostly unique, algorithmic compression can provide better compression results than multivalue compression. Because multivalue compression can coexist with algorithmic compression, users have the flexibility of an IF-ELSE option: either compressing values from a dictionary or using a custom compression algorithm.

Algorithmic compression has a fairly high overhead each time the compressed column is accessed during the execution of a query. It is best used for columns that are used only for the final projected answer set.