In Oracle Database 11g, Data Mining models are implemented as data dictionary objects in the SYS schema. The DMSYS schema will not exist in 11g unless you upgraded from 10g. DMSYS is removed as part of the upgrade to 12c. You can reduce time and complexity for the upgrade by removing DMSYS ahead of the upgrade.

Deinstall

sqlplus / as sysdba;

DROP USER DMSYS CASCADE;

DELETE FROM SYS.EXPPKGACT$ WHERE SCHEMA = 'DMSYS';

SELECT COUNT(*) FROM DBA_SYNONYMS WHERE TABLE_OWNER = 'DMSYS';

If DMSYS Synonyms exist then do this to drop them...

SET HEAD OFF

SET ECHO OFF

SET TRIMSPOOL ON

SPOOL /tmp/DROP_DMSYS_SYNONYMS.SQL

SELECT 'Drop public synonym ' ||'"'||SYNONYM_NAME||'";' FROM DBA_SYNONYMS WHERE TABLE_OWNER = 'DMSYS';

SPOOL OFF

@/tmp/DROP_DMSYS_SYNONYMS.SQL

EXIT;

Bibliography