Why won't Confluence merge concurrent edits?
Asked by Douglas Rapp:

At my organization, we are using Confluence 5.9.7 for online documentation and collaboration. We have run across some peculiar behavior:

If I am editing a page, and then another member of my team starts editing the same page, I get a little notice at the top saying that this other user is making changes. That is good and expected.

However, if that other person hits "Save" before I do, then when I end up trying to save MY changes, Confluence almost always fails to merge them together. The strangeness is that we are editing COMPLETELY different parts of the page.

The result is that a diff screen comes up and I am given the option to either cancel my changes or overwrite the other person's changes. As an example of when this happened recently, I looked at the diff and it showed my additions near the very top of the document. Then, I had to scroll WAAAAY down toward the bottom of the document (pretty large wiki page) to see the other person's edits, which it showed would be removed if I hit the "Overwrite" button.

This seems like a best-case scenario for any sort of merge process. Not only did we not edit the same lines, we didn't even come close to editing the same sections of the document. So why did Confluence fail to merge?

This has happened so many times that my team has resorted to doing their documentation work in Word documents and then coordinating when they will try to copy-paste their changes into the Confluence page so that they don't end up clobbering each other.

It has also caused us to talk with our IT group to upgrade to Confluence 6+ so that we can use the newer collaborative editing feature. But I feel like this shouldn't be necessary for our use-case. Confluence should be able to merge these kinds of edits together.


Answers:
author: AnnWorley
body: Your expectation is correct based on [Concurrent Editing and Merging Changes](https://confluence.atlassian.com/display/conf59/Concurrent+Editing+and+Merging+Changes):

"If Alice clicks save before Bob, Bob is now effectively editing an out-of-date version of the page. When Bob clicks save, Confluence will examine his changes to see if any overlap with Alice's. If the changes don't overlap (i.e. Alice and Bob edited different parts of the page), Bob's changes will be merged with Alice's automatically."

However, since we only fix issues in future releases (we wouldn't patch Confluence 5.9.7) the best bet is to upgrade, as you mentioned.

comments: author: Douglas Rapp
body: So is this a known issue, then?


author: David Stallard
body: I'm experiencing the same thing in 5.10.0 - the second person to click Save is getting a "Not Permitted" message and then their changes are lost. No merge happens, and no special merge conflict screen appears.

I can't find any record of this as a bug. I wondered if maybe some special permission needs to be set to allow merging to work, but haven't found anything on that either.

We are currently planning an upgrade to 6.4.0 so hopefully Collaborative Editing resolves this, but wanted to add my experience since 5.10.0 is not behaving in the way that the "Bob and Alice" example suggests it should.