How to know whether there is N-type columns on database

Below query will return the name of the owner and the table whether there is N-type columns in the database.

SQL> select distinct OWNER, TABLE_NAME from DBA_TAB_COLUMNS where DATA_TYPE
in ('NCHAR','NVARCHAR2', 'NCLOB') order by 1;

OWNER                          TABLE_NAME
------------------------------ ------------------------------
SYS                            ALL_REPPRIORITY
SYS                            DBA_AUDIT_EXISTS
SYS                            DBA_AUDIT_OBJECT
SYS                            DBA_AUDIT_STATEMENT
SYS                            DBA_AUDIT_TRAIL
SYS                            DBA_COMMON_AUDIT_TRAIL
SYS                            DBA_FGA_AUDIT_TRAIL
SYS                            DBA_REPPRIORITY
SYS                            DEFLOB
SYS                            STREAMS$_DEF_PROC
SYS                            USER_AUDIT_OBJECT
SYS                            USER_AUDIT_STATEMENT
SYS                            USER_AUDIT_TRAIL
SYS                            USER_REPPRIORITY
SYSTEM                         DEF$_LOB
SYSTEM                         DEF$_TEMP$LOB
SYSTEM                         REPCAT$_PRIORITY

17 rows selected.

The DBA_FGA_AUDIT_TRAIL comes for Fine Grained Auditing.

ALL_REPPRIORITY, DBA_REPPRIORITY, USER_REPPRIORITY, DEF$_TEMP$LOB , DEF$_TEMP$LOB and REPCAT$_PRIORITY comes for Advanced Replication.

DEFLOB comes for Deferred Transactions functionality.

STREAMS$_DEF_PROC comes for Oracle Streams.

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