Specifies conditions under which data blocks (DBs) for spool and volatile tables will be compressed by default.
Compression is subject to the BlockLevelCompression field setting, and to the criteria specified by the MinPercentCompReduction and MinDBSectsToCompress DBS Control fields. DBs not meeting these minimum criteria will not be compressed.
|ALWAYS||The DBs of a new Spool table will be compressed.|
|NEVER||The DBs of a new Spool table will not be compressed. The Ferret utility COMPRESS command will have no effect.|
|IFNOTCACHED||The DBs of a new table will be compressed if they are not being cached.|
Changes Take Effect
After the DBS Control Record has been written.
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.
Spool includes Persistent Spool used for the Redrive feature.
|For more information on...||See...|
|COMPRESS and UNCOMPRESS commands||Ferret Utility (ferret).|