Normalize Upgrade Install Error (Oracle) ORA-01555

To avoid this error, modify the Oracle UNDO_RETENTION setting. This setting determines how long a query is kept in the UNDO segment. If this setting is low, the UNDO segment is overwritten, which results in ORA-01555.

The UNDO_RETENTION setting must be greater than the longest query (time) to be run by the system.

The following SQL query returns the current setting for UNDO_RETENTION.

select value as "undo_retention in secs"
from v$parameter where name='undo_retention';

BDNA recommends setting the UNDO_RETENTION parameter to 180 minutes, using the following command:

ALTER SYSTEM SET UNDO_RETENTION = 10800 scope=both;

Note:BDNA also recommends the setting UNDO_MANAGEMENT = AUTO, which is the Oracle default.