export data from oracle 10g I installed Oracle 11g on my computer.
When I export data from Oracle 10g, I get the following error code. I have translated the error in parenthesis.

 EXP-00008: 遇到 ORACLE 错误 904  （encouter oracle error 904）
 ORA-00904: "POLTYP": 标识符无效   (POLTYP: is not valid )
 EXP-00000: 导出终止失败           (export fail)


Does someone know why? I believe it is ok to export from Oracle 10g using Oracle 11g client.
Unfortunately not, you cannot export from a 10g database with the 11g client. You can, though, use a dump file from a 10g database (exported with the 10g client) to import into an 11g database (with the 11g client).

Alternatively you can use the newer datapump functionality, and if you create a database link from 11g to 10g you can even transfer the data directly between them without needing to create an intermediate dump file at all.