Re: database character sets utf8

I've run into a similar problem. I tried the following and had a successful conversion:

Login as system/<password>
SQL> SHUTDOWN IMMEDIATE; -- or NORMAL

    <do a full backup>

SQL> STARTUP MOUNT;
SQL> ALTER SYSTEM ENABLE RESTRICTED SESSION;
SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;
SQL> ALTER DATABASE OPEN;
SQL> ALTER DATABASE CHARACTER SET <new_character_set_name>;
SQL> SHUTDOWN IMMEDIATE;   -- or NORMAL
SQL> STARTUP;

dheitholt_at_agency.com (David Heitholt) wrote in message news:<44d2315d.0108161327.31794bcc_at_posting.google.com>...
> I have a question about database character sets.
>
> I need to change an Oracle 8.1.7 database character set from US7ASCII
> to UTF8. The db runs on Solaris 2.8.
>
> My question is: "How to I find out from the database/data dictionary
> and dynamic views what the database's character set is?"
>
> My info source for this topic is the Oracle Generic Doumentation CD
> for 8.1.7 , in particular:
> Oracle8i National Language Support Guide
> Release 2 (8.1.6)
>
> This sentence seemed to answer my question as to where to query to get
> the database's character set:
>
> "NLS_DATABASE_PARAMETERS shows the current NLS parameters of the
> database, including the database character set."
>
> So I do this query:
> SQL> select * from nls_database_parameters
> Where parameter = 'NLS_CHARACTERSET';
> PARAMETER VALUE
> ------------------------------
> ----------------------------------------
> NLS_CHARACTERSET US7ASCII
>
> From this I infer that the database's character set is US7ASCII.
> The info in Oracle Documentation below makes me believe that I can
> change the database character set from US7ASCII to UTF8:
> "For instance, the following migration scenarios can take advantage of
> the ALTER DATABASE CHARACTER SET statement because US7ASCII is a
> strict subset of WE8ISO8859P1, ZHS16GBK, and UTF8:
>
> Table 3-8 Sample Migration Scenarios
> Current Character Set|New Character Set|New Character Set
> is Strict Superset?
> US7ASCII WE8ISO8859P1 Yes
> US7ASCII ZHS16GBK Yes
> US7ASCII UTF8 Yes
>
> So I try the commands to change the character set from US7ASCII to
> UTF8, but they fail with this error:
> SVRMGR> ALTER DATABASE CHARACTER SET UTF8;
> ALTER DATABASE CHARACTER SET UTF8
> *
> ORA-12712: new character set must be a superset of old character set
>
>
> This leads me to believe that either my database's character set is
> not US7ASCII, or the conversion is not possible as described by the
> Oracle documentation.
>
> I find the create script for the database and find that the database
> was created with explicit instructions to set the character set as
> WE8ISO8859P1.
>
> I think that the database's character set is WE8ISO8859P1, but I am
> troubled that the data dictionary views/ dynamic views do not confirm
> this. Any help, explanations, experiences would be appreciated.
> Thanks in advance.
Received on Mon Aug 20 2001 - 13:34:52 CDT