13.2. Using Segment Management Tools
Oracle 10g provides a number of new ways to manage segments in the database. To use disk space more efficiently and to reduce the I/O required to access a segment, segment shrink functionality compacts the space within a segment and optionally moves the high watermark (HWM), freeing up space for other segments.
The Segment Advisor, one of many advisors in Oracle 10g, can analyze one segment or all the segments within a tablespace and determine if a segment is a good candidate for a segment shrink operation. In addition, the Segment Advisor can help you estimate the initial size of a table, as well as predicting growth patterns given your estimates for table inserts, updates, and deletes over time.