Changeing an Oracle database character set

Check what character set you are using at the moment.

SQL> select value from v$nls_parameters where parameter='NLS_CHARACTERSET';

Restrict the database.

SQL> alter system enable restricted session;

Check the current job_queue_processes setting.
```
SQL> show parameter job_queue_processes;
```

Set it to 0 for now.

SQL> alter system set job_queue_processes=0;

Change the character set

SQL> alter database character set WE8MSWIN1252;

Check the job_queue_processes setting.

SQL> show parameter job_queue_processes;

Check the character setting is the new value.

SQL> select value from v$nls_parameters where parameter='NLS_CHARACTERSET';

If necessary, change the job_queue_processes back to what it was.
```
SQL> alter system set job_queue_processes=10;
```
Restart the database.
```
SQL> shutdown immediate;
SQL> startup;
```