17.10 - CompressionLevel - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Database Utilities

Advanced SQL Engine
Teradata Database
Release Number
Release Date
July 2021
Content Type
Publication ID
English (United States)

Determines whether compression operations favor processing speed or degree of data compression.

Field Group


Valid Range

1 through 9

A setting of 1 maximally favors speed of compression operation over degree of data compression. A setting of 9 maximally favors degree of data compression over speed of compression operation.



The default provides a balance between speed of compression operation and degree of data compression.

Changes Take Effect

After the DBS Control Record has been written. Changed setting applies to new data added to tables. Compression for existing data is not changed until that data is modified.

Usage Notes

BLC enables data compression at the data block (DB) level of the Teradata file system. Compression reduces the amount of storage required for a given amount of data. The BlockLevelCompression field of DBS Control enables and disables BLC.

Related Information

For more information on... See...
BlockLevelCompression field BlockLevelCompression.
COMPRESS and UNCOMPRESS commands Ferret Utility (ferret).
BLOCKCOMPRESSION query band Teradata Vantage™ - SQL Data Definition Language Syntax and Examples, B035-1144.