ORA-1555 - UNDO_RETENTION is silently ignored if the LOB resides in a MSSM tablespace

(Doc ID 800386.1)

Last updated on DECEMBER 06, 2016

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 9.0.1 to 11.2]
Information in this document applies to any platform.
***Checked for relevance on 02-Sep-2016***
This problem can occur on any platform.


This may occur when LOB column resides in a MSSM (Manual Segment Space Management) tablespace.

-- Verify Segment Management

select tablespace_name, extent_management,  segment_space_management
from dba_tablespaces
where tablespace_name in
  (select tablespace_name from dba_segments
   where owner='TEST' and segment_name='TAB1');

------------------------------ ---------- ------
TESTCASE                            LOCAL MANUAL <== 

-- Verify LOB retention parameter
select column_name, pctversion, retention
from dba_lobs
where owner = 'TEST' and table_name ='TAB1';

------------- ---------- ----------
DATA                          86400 <==



LOB column is stored on MSSM tablespace.


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