DBA_UNDO_EXTENTS describes the extents comprising the segments in all undo tablespaces in the database.
| Column | Datatype | NULL | Description |
|---|---|---|---|
OWNER |
CHAR(3) |
Owner of the undo tablespace | |
SEGMENT_NAME |
VARCHAR2(30) |
NOT NULL |
Name of the undo segment |
TABLESPACE_NAME |
VARCHAR2(30) |
NOT NULL |
Name of the undo tablespace |
EXTENT_ID |
NUMBER |
ID of the extent | |
FILE_ID |
NUMBER |
NOT NULL |
File identifier number of the file containing the extent |
BLOCK_ID |
NUMBER |
Start block number of the extent | |
BYTES |
NUMBER |
Size of the extent (in bytes) | |
BLOCKS |
NUMBER |
Size of the extent (in blocks) | |
RELATIVE_FNO |
NUMBER |
Relative number of the file containing the segment header | |
COMMIT_JTIME |
NUMBER |
Commit time of the undo in the extent expressed as Julian time. This column is deprecated, but retained for backward compatibility reasons. | |
COMMIT_WTIME |
VARCHAR2(20) |
Commit time of the undo in the extent expressed as Wallclock time. This column is deprecated, but retained for backward compatibility reasons. | |
STATUS |
VARCHAR2(9) |
Transaction Status of the undo in the extent:
|