(Optional) Configuring the character set

AL16UTF16 is the default value of the National Character Set (NLS_NCHAR_CHARACTERSET) for the Oracle database. Cloudera recommends that you use the default NLS_NCHAR_CHARACTERSET. However, if needed, you can configure the National Character Set to UTF-8.

Log in as the oracle user:
```
su - oracle
```
Start the listener control (as user oracle):
```
$ORACLE_HOME/bin/lsnrctl start
```
Log in to SQL*Plus:
```
sqlplus / as sysdba
```

Check whether the character set is AL32UTF8 and national character set is UTF8:

SELECT * FROM v$nls_parameters where parameter like '%CHARACTERSET';

To update, quit the shell and run these commands in a SQL*Plus script:

vi alter_charset.ddl

## Save in alter_charset.ddl (script takes 2-3 minutes)
CONNECT / as sysdba
SHUTDOWN immediate
STARTUP mount
ALTER SYSTEM ENABLE RESTRICTED SESSION;
ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0 SCOPE = MEMORY;
ALTER SYSTEM SET AQ_TM_PROCESSES=0 SCOPE = MEMORY;
ALTER DATABASE OPEN;
ALTER DATABASE CHARACTER SET AL32UTF8;
ALTER DATABASE NATIONAL CHARACTER SET INTERNAL_USE UTF8;
SHUTDOWN immediate
STARTUP

sqlplus /nolog < alter_charset.ddl