17.10 - MinPercentCompReduction - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - Database Utilities

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Configuration
Publication ID
B035-1102-171K
Language
English (United States)

Specifies the minimum percentage by which the data block (DB) size must be reduced by compression. If compression will not reduce the DB by at least this amount, the DB will not be compressed, because the overhead of having to compress and uncompress the blocks during DML operations is not worth the minimal space savings that might be achieved.

Field Group

Compression

Valid Range

0 through 99 percent

Default

20 percent

Changes Take Effect

After the DBS Control Record has been written.

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.

Compression is also subject to the criteria specified by the MinDBSectsToCompress DBS Control setting. DBs not meeting these minimum criteria will not be compressed, even if they are larger than the size specified by MinPercentCompReduction.

Related Information

For more information on... See...
COMPRESS and UNCOMPRESS commands Ferret Utility (ferret).