To change the location of all the datafiles

[davey23uk]

Use ALTER DATABASE RENAME FILE 'old_name' TO 'new_name';

Start the instance to mount state and rename all files you moved
including datafiles, online log files and tempfiles.
The old names you get from controfile with these queries:

select name from v$datafile;
select member from v$logfile;
select name from v$tempfile;

You also need to adjust pfile/spfile if the controlfiles moved.

the problem with that is havign run a command many times or doing some code to loop round all the files

doing a global replace in a control file is much easier