I have come across this discussion about the problems caused when two people want to update the same node at the same time. However it is not clear to me what the status of this is in Drupal 4.5.0. Did any of the patches make it into core?
More generally, I'm inclined to think that this discussion misses the main point. The proposed patches may stop people overwriting each other's updates - however, this only fits the use case where two people doing simultaneous updates on the same content is something exceptional.
If you are really running a site where multiple people may potentially be editing the same content, then IMHO what you require is a "check-out/check-in" solution. In other words:
- Alice presses the edit button for a node
- Drupal immediately updates the node to show that it is in the process of being edited by Alice
- Bob presses the edit button for the same node: an error message informs him that he cannot edit it, because it is "checked out" by Alice
- Alice finishes editing: on Alice's edit form, there is a checkbox which allows her to choose
---- either to submit the node and check it back in (ie it becomes available for others to edit)
---- or to submit the node while leaving it checked out (ie it remains locked for editing as far as other users are concerned - only Alice can come back and edit the node again).
If Alice leaves the node checked out, then it might be an idea to make the "log message" an obligatory field (if available) and display this to other users trying to edit, so that they know what Alice is doing.