分类： Oracle
2009-07-08 11:55:30
Free space can be managed automatically or manually.
Free space can be managed automatically inside database segments. The in-segment free/used space is tracked using bitmaps, as opposed to free lists. Automatic segment-space management offers the following benefits:
Ease of use
Better space utilization, especially for the objects with highly varying row sizes
Better run-time adjustment to variations in concurrent access
Better multi-instance behavior in terms of performance/space utilization
You specify automatic segment-space management when you create a locally managed tablespace. The specification then applies to all segments subsequently created in this tablespace.
