16.10 - TempBLCInterval - Teradata Database

Teradata Database Utilities

Product
Teradata Database
Release Number
16.10
Published
June 2017
Language
English (United States)
Last Update
2018-04-26
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Purpose

Specifies the amount of time in minutes that the background temperature-based block-level compression (TBBLC) task waits after compressing or uncompressing data before checking for other data to process. This field is effective only when TBBLC is enabled.

Field Group

Compression

Valid Range

1 through 120 minutes

Default

10 minutes

Changes Take Effect

The first time the background compression task runs after the DBS Control Record has been written.

Usage Notes

If the whole MI is scanned and no data requires compressing or uncompressing, AutoTempComp sleeps for a period defined by TempBLCRescanPeriod before checking again.

BLC enables data compression at the data block (DB) level of the Teradata Database 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.

Data temperature refers to the frequency of access. Hot data is frequently accessed. Cold data is infrequently accessed. Warm data is accessed moderately frequently. TBBLC automatically compresses colder data to save storage space, and decompresses the data if it becomes hotter. At any time, different portions of a table, such as different partitions, may exist in different states of compression depending on their temperatures.

Related Topics

For more information on… See…
Block-Level Compression Database Design
BLOCKCOMPRESSION table attribute SQL Data Definition Language - Syntax and Examples
Enabling TBBLC EnableTempBLC
Ferret COMPRESS, UNCOMPRESS, and FORCE commands Ferret Utility (ferret)
Query bands for compression SQL Data Definition Language - Syntax and Examples
Storage group of DBS Control fields Storage Group