if you look at the various releases of Oracle, up til the current one (10g), you can see that Oracle has been working on this -- for a perfect example, check out the transportable tablespace feature. initially very limited, but now (in 10g) quite useful. therefore, it is obvious that certain "tricks" work in certain releases. this having said, what you describe below in highly unsupported -- which means that you are completely on your own (i.e. no support) if things go wrong. hope this helps, kind regards, Lex. ---------------------------------------------------------------- Tom Kyte Seminar: http://www.naturaljoin.nl/events/seminars.html ---------------------------------------------------------------- -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of biti_rainy Sent: Thursday, January 20, 2005 07:24 To: oracle-l Subject: (NEW) very interesting thing about migrate db from different OS(oracle 9.2.0.4,not 10G) hi,all we find a very interesting thing: we copy the WINDOWS2000 datafile to linux (they have the same byte order) and , dd a linux datafile header to cover the windows datafile header(the header block is not include in dba_data_files),the block is not seem in database ,it is for OS. ls -l can see ,the datafile size is bigger than dba_data_files for one oracle block. when we change the OS file header,we can create controlfile and open the database ,and we can query /create table ... etc. the db version is oracle9204,not 10g. and someone told me that he can copy the datafile from windows and solaris for x86 pc to linux , and not change the header with oracle8i. is there someone can discuss it? Best regards msn: biti_rainy@xxxxxxxxxxx a dba from alibaba(china) -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l