Hi,

Free space are not getting reflecting in the view DBA_FREE_SPACE for the tablespace UNDO.

TOTAL SPACE ALLOCATED FOR UNDO TABLESPACE
=========================================
ADMIN@PROD>SELECT SUM(BYTES)/1024/1024 "MB" FROM DBA_DATA_FILES
2 WHERE TABLESPACE_NAME ='UNDODATA';

MB
----------
46500

Free space calculation based on DBA_FREE_SPACE view
====================================================
1 SELECT SUM(BYTES)/1024/1024 "MB" FROM DBA_FREE_SPACE
2* WHERE TABLESPACE_NAME ='UNDODATA'
ADMIN@PROD>/

MB
----------
.875

verifying the same on the view DBA_UNDO_EXTENTS
===============================================

ADMIN@PROD>SELECT SUM(BYTES)/1024/1024 "MB" FROM DBA_UNDO_EXTENTS;

MB
----------
28638.3984

1 row selected.

ADMIN@PROD>SELECT SUM(BYTES)/1024/1024 "MB" ,STATUS FROM DBA_UNDO_EXTENTS
2 GROUP BY STATUS;

MB STATUS
---------- ---------
64 ACTIVE
4858.32031 EXPIRED
23716.0781 UNEXPIRED

3 rows selected.

ADMIN@PROD>SHO PARAMETER UNDO

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO
undo_retention integer 23244
undo_suppress_errors boolean FALSE
undo_tablespace string UNDODATA


QUESTION:-
=============
1. Based on DBA_UNDO_EXTENTS totalspace used on UNDO tablespace is 28638 MB, hence freespace avail
(totalspace - usedspace)

46500 - 28638 = 17862 MB ( Freespace in UNDO tablespace).

But when verifying the DBA_FREE_SPACE,the above value is not reflecting and its showing only .875 MB free.

Could you please give background of this.

Thanks,
Adhi