Use OLEDB in Chinese windows Server

Question

Hello..
I have a problem in using OLEDB in Chinese windows system.
If i write sql statement that include Chinese Language in ASP code, then I can not return record correctly.
For example,in case of col1 of table1 is varchar2 type and data inserted chinese language, if i execute query that 'select col1 from table1' then has no problem.
but i execute 'select col1 from table1 where col1 = 'CHINESE LANGUAGE' then return no record..
How can i fix it?
Environment :
Windows 2000 Advanced Server with SP4
Web server - IIS 5.x
MDAC version - 2.53.6200.1
Oracle version - 8.1.7.4.1
Oracle Provider for OLE DB - 8.1.7.3.0
Oracle NLS - AMERICAN_AMERICA.US7ASII

Answer 1

The characterset is a problem, but it's a common problem.
Taking a step back and thinking about the problem logically, it should be clear that you shouldn't be able to store Chinese data in a US7ASCII database. A US7ASCII database can store 128 distinct characters, but there are a whole lot more than 128 Chinese characters. If every character in the world could be represented via ASCII, Unicode would have been a pointless exercise.
Why, then, does it appear to work correctly for you? When the client and the server both have the same NLS language setting, the Oracle networking layer doesn't do any sort of character set conversion-- it just passes the data back and forth as a binary stream. In your case, the client application is, in essence, lying to the database about the type of data it's passing in. In all probability, you really have Big5 encoded data. So long as the retrieving application expects to be getting that same encoding (Big5), and doesn't bother to ask the client what encoding it's actually getting back, everything will appear to work. You're pulling a fast one on the database, but as long as everyone is in on the lie, everything will work.
The problem comes, however, when other applications believe the lie that the database is telling. When the OLE DB provider retrieves the data, it knows that it's going to want Unicode data. Since the database claims to be storing ASCII data, the Oracle networking layer will attempt to convert the "ASCII" data to Unicode before handing it to the ASP page. Since the data really isn't ASCII, though, the conversion won't work. The same sort of thing would happen if you used some of the Oracle tools like export & import or if you queried the data from an English Windows system that's set up to handle Unicode data.
At this point, you have corrupt data in the database. You don't have valid Chinese in the database.
Justin
Distributed Database Consulting, Inc.
www.ddbcinc.com