Unreadable Charactors (?????) - Oracle to SQL Server 2005 Database

Question

Hi everybody:
I have some trouble in Oracle Database client and SQL Server 2005,when I
SELECT some table(in that table have some japanese charactors and these
table are in SQL Server 2005 ) in Oracle Database client.And I have some
errors as follows:
ORA-28500: connection from ORACLE to a non-Oracle system returned this
message: [Generic Connectivity Using ODBC]DRV_GetRows:
preceding 2 lines from MSQL3 Cause
And the detail description are as following:
1. Table A in SQL Server 2005 has datatype as nchar. Data stored in this
table are Japanese charactors, for eg カラー, 品番, etc and some are
English charactors.
2. ODBC version 2000.81.9002.00 is set in Oracle Server.
3. a) Connection to SQL Server 2005 (as mentioned in Point 1) is done
through a database link object, named MSQL on Oracle 10G.
b) NLS_CHARACTERSET in 10G is UTF8.
c) NLS_NCHAR_CHARACTERSET in 10G is AL16UTF16
4. We use PL/SQL DEVELOPER 7.0 and client's unicode is set as UTF8.
Problem:
Sometimes We keep on getting unreadable charactors (ie ?????) when we use PL/SQL
to run queries from Table A.But other sometimes we have the error as above
i.e
ORA-28500: connection from ORACLE to a non-Oracle system returned this
message: [Generic Connectivity Using ODBC]DRV_GetRows:
preceding 2 lines from MSQL3 Cause
However, no problem found so far for English charactors.
Thank you very much.

Answer 1

Hi Ushitaki
Thank you again .
What kind of developer tools do you use with on trying that?
We use PL/SQL DEVELOPER 7.0 ,and we also have tried Toad developer tools ,no matter what tools the problem still exist....
On the other hand we set NLS_LANG and set the windows codepage 932 and 936 ,too.But it's a pity we still get the error.
and the error as follows :
ORA-28500: connection from ORACLE to a non-Oracle system returned this
message: [Generic Connectivity Using ODBC]DRV_GetRows:
preceding 2 lines from MSQL3 Cause
Message was edited by:
user569423