How can I combine two datafile into one?

Our previous DBA used two datafiles for SYSTEM tablespace (say datafile1 20M, 5 M used and datafile2 50M, 2 M used). It seems odd to me since I think one is easier to manage and should be more efficient. Anyway, how can I combine them into only one file?

Thanks

Jizhong Received on Tue Sep 23 1997 - 00:00:00 CDT