dba_undo_extents
Name Null? Type
---------------- -------- ------------
OWNER CHAR(3)
SEGMENT_NAME NOT NULL VARCHAR2(30)
TABLESPACE_NAME NOT NULL VARCHAR2(30)
EXTENT_ID NUMBER
FILE_ID NOT NULL NUMBER
BLOCK_ID NUMBER
BYTES NUMBER
BLOCKS NUMBER
RELATIVE_FNO NUMBER
COMMIT_JTIME NUMBER
COMMIT_WTIME VARCHAR2(20)
STATUS VARCHAR2(9)
Describes all undo extents in system managed undo tablespaces. Use the following query to get an overview of your undo extents:
select tablespace_name
, status
, count(*) as HOW_MANY
from dba_undo_extents
group by tablespace_name
, status
/
You will see output similar to this:
TABLESPACE_NAME STATUS HOW_MANY
------------------------------ --------- ----------
UNDO EXPIRED 33
UNDO UNEXPIRED 15
The meaning of the values in the status column are as follows:
- ACTIVE - There is an active transaction using this undo extent.
- EXPIRED - The extent can be reused.
- UNEXPIRED - There are no active transactions, but the extent is not available for reuse.
For more useful DBA queries click here.
| 