Base ClearCase FAQ 1.7.4: subversion has the concept of atomic check-ins. Does clearcase have this capability?

With subversion atomic check-ins, a complete set of files are checked in as a single version and they either all make it in or none do. It also makes it very easy to rollback a large commit

Answer

Subversion uses the same terms as ClearCase, but in a misleading way:

checkout:

In subversion, you checkout a whole sub-tree, just to populate your working copy, e.g. for building, even with no intention to change anything.

Not so in ClearCase (with dynamic views—I skip snapshot views for now). ClearCase manages your workspace (subversion does not). What you build there is by default shared with others, and visible. 'Checkout' in ClearCase is only to modify, and has thus no equivalent in subversion.

checkin/commit:

In subversion, this is the publication of a change.

The nearest equivalent in ClearCase is applying a label, although this is already a process issue. You get the atomicity with locking the label type. ClearCase offers support for multiple processes (unless one uses UCM...) whereas subversion doesn't really: all the processes boil down more or less to sharing a synchronous baseline (there may be a few, but there is no real support for managing many).

-- MarcGirod - 03 Jul 2008