I didn't know US7ASCII could store Chinese. Interesting.
Why not use AL32UTF8? Oracle promises to keep it in sync with the latest Unicode standard, currently at version 4, while UTF8 stops at version 3.
Yong Huang
yes, by right, US&ASCII can not store Chinese character. But if you define your database character set to US7ASCII and input Chinese character, most of the chinese characters should be ok.
I have to say the DBA who installed Oracle Database couple of years ago made such insane decision, and so far as too many applications running on this DB it's not easy to just shutdown the database and reinstall to make everything right.
other than the convert function, is there any other idea?
To answer your original question, I'm pretty sure you'll be OK to change characterset from US7ASCII to UTF8, and probably OK to change to GB2312. Export and import should be OK too. Why not create a small database of UTF8 or GB2312 and import data into it?
Yong Huang
