How to change character set

Question

hi my database character set is non-AL32UTF8 HOW can i change this to be AL32UTF8 am in database 11g
SQL> select * from v$nls_parameters where parameter like '%CHARACTERSET%';
PARAMETER
VALUE
NLS_CHARACTERSET
WE8MSWIN1252
NLS_NCHAR_CHARACTERSET
AL16UTF16
there is something in database i cannot drop database

Answer 1

i did this
SQL> @C:\app\Tshifhiwa\product\11.2.0\dbhome_1\RDBMS\ADMIN\csalter.plb
insert into csm$dictusers
ERROR at line 1:
ORA-00942: table or view does not exist
Function created.
Warning: Function created with compilation errors.
Warning: Procedure created with compilation errors.
This script will update the content of the Oracle Data Dictionary.
Please ensure you have a full backup before initiating this procedure.
Would you like to proceed (Y/N)?y
old   6:     if (UPPER('&conf') <> 'Y') then
new   6:     if (UPPER('y') <> 'Y') then
    csm$main();
ERROR at line 10:
ORA-06550: line 10, column 5:
PLS-00905: object SYS.CSM$MAIN is invalid
ORA-06550: line 10, column 5:
PL/SQL: Statement ignored
    select value into svalue from csm$parameters where name='CSALTER_FINISHED';
ERROR at line 9:
ORA-06550: line 9, column 35:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 9, column 5:
PL/SQL: SQL Statement ignored
ORA-06550: line 18, column 35:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 18, column 5:
PL/SQL: SQL Statement ignored
ORA-06550: line 21, column 38:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 21, column 8:
PL/SQL: SQL Statement ignored
ORA-06550: line 27, column 35:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 27, column 5:
PL/SQL: SQL Statement ignored
ORA-06550: line 30, column 38:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 30, column 8:
PL/SQL: SQL Statement ignored
delete from csm$dictusers where username in ('PM', 'SH', 'HR', 'OE')
ERROR at line 1:
ORA-00942: table or view does not exist
Function dropped.
Function dropped.
Procedure dropped.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> ALTER SYSTEM ENABLE RESTRICTED SESSION;
ALTER SYSTEM ENABLE RESTRICTED SESSION
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;
ERROR:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
SQL> ALTER SYSTEM SET AQ_TM_PROCESSES=0;
ERROR:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
ALTER SYSTEM SET AQ_TM_PROCESSES=0
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;
ERROR:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 4360
Session ID: 139 Serial number: 6
SQL> connect /as sysdba
Connected to an idle instance.
SQL> startup mount;
ORACLE instance started.
Total System Global Area  535662592 bytes
Fixed Size                  1375792 bytes
Variable Size             373293520 bytes
Database Buffers          155189248 bytes
Redo Buffers                5804032 bytes
Database mounted.
SQL> ALTER SYSTEM ENABLE RESTRICTED SESSION;
System altered.
SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;
System altered.
SQL> ALTER SYSTEM SET AQ_TM_PROCESSES=0;
System altered.
SQL> ALTER DATABASE OPEN;
Database altered.
SQL> ALTER DATABASE CHARACTER SET 'AL32UTF8';
ALTER DATABASE CHARACTER SET 'AL32UTF8'
ERROR at line 1:
ORA-24329: invalid character set identifier
SQL> ALTER DATABASE CHARACTER SET AL32UTF8;
ALTER DATABASE CHARACTER SET AL32UTF8
ERROR at line 1:
ORA-12712: new character set must be a superset of old character set
SQL> select * from v$nls_parameters where parameter like '%CHARACTERSET%';
PARAMETER
VALUE
NLS_CHARACTERSET
WE8MSWIN1252
NLS_NCHAR_CHARACTERSET