Progress
Database Administration
Guide and Reference
Compacting Indexes
When space utilization of an index is reduced to 60% or less as indicated by the PROUTIL IDXANALYS utility, use the PROUTIL IDXCOMPACT utility to perform index compaction online. Performing index compaction increases space utilization of the index block to the compacting percentage specified. For example:
NOTE: For the complete syntax description see Database Administration Utilities."Performing index compaction reduces the number of blocks in the B-tree and possibly the number of B-tree levels, which improves query performance.
The index compacting utility operates in phases:
The _UserStatus virtual system table displays the utility's progress. For more information see Maintaining Database Structure."
NOTE: Because index compacting is performed online, other users can use the index simultaneously for read or write operation with no restrictions. Index compacting only locks 1 to 3 index blocks at a time, for a short time. This allows full concurrency.
Copyright © 2004 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095 |