ORA-01145

Error: ORA-01145: offline immediate disallowed unless media recovery enabled

Causa: ALTER TABLESPACE ... OFFLINE IMMEDIATE or ALTER DATABASE DATAFILE ... OFFLINE is only allowed if the database is in ARCHIVELOG mode.

Acción: Take the tablespace offline as usual or do a shutdown abort before attempting the required operation. It is worthwhile reconsidering the backup strategy for the database. The attempted operations can be done if ARCHIVEREDO LOG mode is enabled.