Maintaining data organization
Data that is physically well-organized can improve the performance of access paths that rely on index or table scans, and reduce the amount of disk storage used for the data.
About this task
Depending
on the number of changes, you might encounter performance degradations
for the following types of operations when your data becomes disorganized:
- Dynamic SQL queries.
- Updates and deletes. For example, delete operations sometimes result in pseudo-deleted index entries, which can result in additional lock contention. You can reduce the necessity of frequently reorganizing your data by enabling automated index cleanups.
- ALTER statements (especially those that run concurrently).
- Concurrent REORG and LOAD utilities.
- Unloading a table that has had many changes before reorganization.
Procedure
To determine when to reorganize your data, use any of the following approaches: