16.20 - Usage Notes - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Operators and User-Defined Functions

Advanced SQL Engine
Teradata Database
Release Number
April 2020
Content Type
Programming Reference
Publication ID
English (United States)
Last Update

Uncompressed character data in Teradata Database requires 2 bytes per character when storing Unicode data. CAMSET takes Unicode character input, compresses it into partial byte, one byte, or two byte values, and returns the compressed result.

CAMSET provides best results for short or medium Unicode strings that:

  • contain mainly digits and English alphabet letters.
  • do not frequently switch between:
    • lowercase and uppercase letters.
    • digits and letters.
    • Latin and non-Latin characters.

Although you can call the function directly, CAMSET is normally used with algorithmic compression (ALC) to compress table columns. If CAMSET is used with ALC, nulls are also compressed if those columns are nullable.