DBA_DMT_USED_EXTENTS describes the extents comprising the segments in all dictionary managed tablespaces in the database.
| Column | Datatype | NULL | Description |
|---|---|---|---|
SEGMENT_FILEID |
NUMBER |
NOT NULL |
File number of the segment header of the extent |
SEGMENT_BLOCK |
NUMBER |
NOT NULL |
Block number of the segment header of the extent |
TABLESPACE_ID |
NUMBER |
NOT NULL |
Identifier number of the tablespace containing the extent |
EXTENT_ID |
NUMBER |
NOT NULL |
Extent number in the segment |
FILEID |
NUMBER |
NOT NULL |
File identifier number of the file containing the extent |
BLOCK |
NUMBER |
NOT NULL |
Starting block number of the extent |
LENGTH |
NUMBER |
NOT NULL |
Number of blocks in the extent |