MANUAL: Manual segment-space management uses free lists to manage free
space within segments. Free lists are lists of data blocks that have space
available for inserting rows. With this form of segment-space management, you
must specify and tune the PCTUSED, FREELISTS, and FREELIST GROUPS
storage parameters for schema objects created in the tablespace. MANUAL is the
default.
AUTO: Automatic segment-space management uses bitmaps to manage the free
space within segments. The bitmap describes the status of each data block
within a segment with respect to the amount of space in the block available for
inserting rows. As more or less space becomes available in a data block, its new
state is reflected in the bitmap. These bitmaps allow the database to manage
free space automatically.
