Check-in all files at a time?

[yerra babji]

Hi,

     Is there any way to mandate svn users to check in all the files they
modified? ( Some  times they don't want to check-in some files in that case
they can revert those files and check all the required files)

I came across concept of change set to check-in multiple files as a bundle(
at a time) is there any way to restrict users to check in only change sets
only. ( getting the effect of transaction set )

Thanks,
Babji