[oracle@einyboy ~]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.1.0 - Production on Wed Jul 25 12:21:02 2012
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Connected to:Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - ProductionWith the Partitioning, OLAP and Data Mining optionsSQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------undo_management string AUTOundo_retention integer 900undo_tablespace string UNDOTBS1SQL> alter system set undo_retention=1200 scope=both;System altered.
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------undo_management string AUTOundo_retention integer 1200undo_tablespace string UNDOTBS1SQL>