Export/import character data conversion in NLS_LANG FAQ

Question

The [OTN NLS_LANG FAQ|http://www.oracle.com/technology/tech/globalization/htdocs/nls_lang%20faq.htm#_Toc110410566] says:
>
In Oracle9i the Export utility always exports user data, including Unicode data, in the character set of the database. The Import utility automatically converts the data to the character set of the target database.
>
But I don't think this is correct for Oracle 9i. Example:
export NLS_LANG=AMERICAN_AMERICA.US7ASCII
sqlplus /
SQL*Plus: Release 9.2.0.6.0 - Production on Wed Jun 17 10:05:57 2009
Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.
Connected to:
Oracle9i Enterprise Edition Release 9.2.0.6.0 - 64bit Production
JServer Release 9.2.0.6.0 - Production
SQL> select * from v$version;
BANNER
Oracle9i Enterprise Edition Release 9.2.0.6.0 - 64bit Production
PL/SQL Release 9.2.0.6.0 - Production
CORE    9.2.0.6.0       Production
TNS for HPUX: Version 9.2.0.6.0 - Production
NLSRTL Version 9.2.0.6.0 - Production
SQL> select * from nls_database_parameters where parameter like '%SET%';
PARAMETER                      VALUE
NLS_CHARACTERSET               WE8ISO8859P15
NLS_NCHAR_CHARACTERSET         AL16UTF16
SQL> exit
Disconnected from Oracle9i Enterprise Edition Release 9.2.0.6.0 - 64bit Production
JServer Release 9.2.0.6.0 - Production
exp / owner=test file=test.dmp
Export: Release 9.2.0.6.0 - Production on Wed Jun 17 10:06:42 2009
Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.
Connected to: Oracle9i Enterprise Edition Release 9.2.0.6.0 - 64bit Production
JServer Release 9.2.0.6.0 - Production
Export done in US7ASCII character set and AL16UTF16 NCHAR character set
server uses WE8ISO8859P15 character set (possible charset conversion)
About to export specified users ...Could you please:
- check and update NLS_LANG FAQ for Oracle 9i
- update NLS_LANG FAQ for Oracle 10g, Oracle 11g and Data Pump.
Thanks.
Edited by: P. Forstmann on Jun 17, 2009 10:14 AM

Answer 1

I was wrong and you are right like the OTN NLS_LANG FAQ.
I made the following test with Oracle 9.2.0.6 and with Oracle XE:
sqlplus test/test
SQL*Plus: Release 10.2.0.1.0 - Production on Ven. Juin 19 10:20:23 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connecté à :
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> create table t (x varchar2(10));
Table créée.
SQL> insert into t values(chr(233));
1 ligne créée.
SQL> select * from t;
X
é
SQL> select dump(x,1017) from t;
DUMP(X,1017)
Typ=1 Len=1 CharacterSet=WE8MSWIN1252: e9
SQL> exit
Déconnecté de Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
set NLS_LANG=AMERICAN_AMERICA.US7ASCII
exp test/test tables=t file=t.dmp
Export: Release 10.2.0.1.0 - Production on Fri Jun 19 10:21:54 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to: Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
Export done in US7ASCII character set and AL16UTF16 NCHAR character set
server uses WE8MSWIN1252 character set (possible charset conversion)
About to export specified tables via Conventional Path ...
. . exporting table                              T          1 rows exported
Export terminated successfully without warnings.
sqlplus test/test
SQL*Plus: Release 10.2.0.1.0 - Production on Fri Jun 19 10:22:07 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> drop table t;
Table dropped.
SQL> exit
Disconnected from Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
imp test/test tables=t file=t.dmp
Import: Release 10.2.0.1.0 - Production on Fri Jun 19 10:22:23 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to: Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
Export file created by EXPORT:V10.02.01 via conventional path
import done in US7ASCII character set and AL16UTF16 NCHAR character set
import server uses WE8MSWIN1252 character set (possible charset conversion)
. importing TEST's objects into TEST
. importing TEST's objects into TEST
. . importing table                            "T"          1 rows imported
Import terminated successfully without warnings.
sqlplus test/test
SQL*Plus: Release 10.2.0.1.0 - Production on Fri Jun 19 10:22:32 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL>  select dump(x,1017) from t;
DUMP(X,1017)
Typ=1 Len=1 CharacterSet=WE8MSWIN1252: e9