Encoding problem with convert and CLOB involving UTF8 and EBCDIC

Question

Hi,
I have a task that requires me to call a procedure with a CLOB argument containing a string encoded in EBCDIC. This did not go well so I started narrowing down the problem. Here is some SQL to illustrate it:
SQL> select * from v$version;
BANNER
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
PL/SQL Release 10.2.0.4.0 - Production
CORE 10.2.0.4.0 Production
TNS for Solaris: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production
SQL> select value from v$nls_parameters where parameter = 'NLS_CHARACTERSET';
VALUE
AL32UTF8
SQL> select convert(convert('abc', 'WE8EBCDIC500'), 'AL32UTF8', 'WE8EBCDIC500')
output from dual;
OUT
abc
SQL> select convert(to_char(to_clob(convert('abc', 'WE8EBCDIC500'))), 'AL32UTF8', 'WE8EBCDIC500') output from dual;
OUTPUT
╒╫¿╒╫¿╒╫¿
So converting to and from EBCDIC works fine when using varchar2, but (if I am reading this right) fails when involving CLOB conversion.
My question then is: Can anyone demonstrate how to put correct EBCDIC into a CLOB and maybe even explain why the examples do what they do.

Answer 1

in order to successfully work with xmldb it is recommended that you use 9.2.0.4
and above. Its seems to have lower version.
Okay now related to the problem , if your data that you want to send to the attributes are not greater than 32767, then you can use the pl/sql varchar2 datatype to hold the data rather then CLOB and overcome this problem.
here is the sample. use function with below pl/sql to return the desired output.
SQL> declare
  2   l_clob     CLOB := 'Hello';
  3   l_output   CLOB;
  4  begin
  5    select  xmlelement("test", xmlattributes(l_clob AS "a")).getclobval()
  6      into l_output from dual;
  7  end;
  8  /
  select  xmlelement("test", xmlattributes(l_clob AS "a")).getclobval()
ERROR at line 5:
ORA-06550: line 5, column 44:
PL/SQL: ORA-00932: inconsistent datatypes: expected - got CLOB
ORA-06550: line 5, column 3:
PL/SQL: SQL Statement ignored
SQL> declare
  2   l_vchar     varchar2(32767) := 'Hello';
  3   l_output   CLOB;
  4  begin
  5    select  xmlelement("test", xmlattributes(l_vchar AS "a")).getclobval()
  6      into l_output from dual;
  7    dbms_output.put_line(l_output);
  8  end;
  9  /
<test a="Hello"></test>
PL/SQL procedure successfully completed.