Home
AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Administrator's GuideThe HCL OneDB™ Administrator's Guide provides the information required to administer HCL OneDB™.
Disk, memory, and process management
Manage disk spaceYou can use several utilities and tools to manage disk spaces and the data that the database server controls.
Storage optimizationData compression and consolidation processes can minimize the disk space that is used by your data and indexes.Data compression and consolidation processes can minimize the disk space that is used by your data.
CompressionYou can compress and uncompress row data in tables and fragments and simple large objects in dbspaces. You can compress B-tree indexes.You can compress data in tables and table fragments to reduce the amount of disk space. You can also consolidate free space in a table or fragment and you can return this free space to the dbspace. Before you compress data, you can estimate the amount of disk space that you can save.
BLOBspace Blob Compression A partition BLOB (binary large object) column is a TEXT or BYTE column that is stored in a DBspace, in the same RSAM partition as the home row. A BLOBspace BLOB column is the same data type (TEXT or BYTE), but the BLOB data is stored in a BLOBspace.

BLOBspace Blob Compression

A partition BLOB (binary large object) column is a TEXT or BYTE column that is stored in a DBspace, in the same RSAM partition as the home row. A BLOBspace BLOB column is the same data type (TEXT or BYTE), but the BLOB data is stored in a BLOBspace.

All TEXT and BYTE BLOBs may be compressed, whether they are stored in the partition or a BLOBspace. If a table containing TEXT or BYTES columns is created with the COMPRESSED keyword, the BLOB data will be automatically compressed along with the home row data once the number of rows has reached a certain threshold (2000 by default). Separate compression dictionaries are built for the home rows and each BLOB column.

By using the "compress" sysadmin task() command rather than the auto compress feature, it is possible to compress only the BLOB data in a table, or to compress only the home row data without compressing BLOBs.
ER is able to replicate BLOB data whether it is compressed or uncompressed.

Have feedback?
Google Analytics is used to store comments and ratings. To provide a comment or rating for a topic, click Accept All Cookies or Allow All in Cookie Preferences in the footer of this page.