17.10 - Usage Notes - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Operators and User-Defined Functions

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Administration
Programming Reference
Publication ID
B035-1210-171K
Language
English (United States)

Uncompressed character data in Vantage requires 2 bytes per character when storing Unicode data. LZCOMP takes Unicode character input, compresses it using the Lempel-Ziv algorithm, and returns the compressed result.

LZCOMP provides good compression results for long Unicode strings, but might not be as effective for short strings. It can also provide good results for medium strings that have many repeating characters.

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