How can I determine if my Oracle system is installed to support Unicode characters or multibyte characters?

Question

I understand that Oracle supports multiple character sets, but how do I determine if the current 11g system I'm working on supports this functionality?

Answer 1

SELECT * FROM v$nls_parameters WHERE parameter LIKE '%CHARACTERSET'; 

will show you the database and the national character set. The database character set controls the encoding of the data in the CHAR and VARCHAR2 . If the database supports Unicode in these columns, the database character set must be AL32UTF8 (or UTF8 in some rare cases). The national character set controls the encoding of data in the NCHAR and NVARCHAR2 . If the database character set does not support Unicode, you can store Unicode data in columns with these data types, but this usually complicates the work of the system - perhaps applications should be changed to support the national character set.

Answer 2

Unicode is a character encoding system that defines each character in most spoken languages ​​in the world. Unicode support in Oracle database:

 Character Set Supported in RDBMS Release Unicode Encoding AL24UTFFSS 7.2 - 8i UTF-8 UTF8 8.0 - 11g UTF-8 UTFE 8.0 - 11g UTF-EBCDIC AL32UTF8 9i - 11g UTF-8 AL16UTF16 9i - 11g UTF-16 

To make sure your database is Unicode, check the value of the NLS_CHARACTERSET parameter and it should be AL32UTF8 or AL16UTF16 from the list above.

 SQL> SQL> SELECT * FROM v$nls_parameters WHERE parameter='NLS_CHARACTERSET'; PARAMETER VALUE CON_ID --------------------------- ------------------- ---------- NLS_CHARACTERSET AL32UTF8 0 

To change the value of a parameter, please take Fullback, because the ALTER DATABASE statement cannot be undone and the following statements are used:

 SHUTDOWN IMMEDIATE STARTUP MOUNT; ALTER SYSTEM ENABLE RESTRICTED SESSION; ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0; ALTER SYSTEM SET AQ_TM_PROCESSES=0; ALTER DATABASE OPEN; ALTER DATABASE CHARACTER SET AL32UTF8; SHUTDOWN IMMEDIATE; STARTUP;