Can we please have some way to undo merges?

Question

I am well aware that merges cannot currently be undone, but I really think this should probably be a priority. I can see many possibilities of a merge creating a tricky tangle that is very hard to undo. For example take a look at the profile Brooks-1273 which was recently merged into Richardson-1577. If Richardson-1577  and the prior version of Brooks-1273 was kept in some buffer or temporary database then the reconstruction would be much simpler. I enjoy the collaboration here, and I know that sometime down the road I will inadvertently do something I should not. AND, as wikitree grows, the possibilities of tangling things up in a nearly unrecoverable way will grow exponentially.

Just my 2 cents.

Answer 1

Hi Toby,

We will continue to work on solutions as problems emerge.

An "un-do" button for merges would be tricky because other changes may have happened after the merge. X was merged into Y. Then Y was edited. X's old family members were edited, etc.

We could set it so that the un-do function would only work if no edits were made to Y after the merge *and* no edits were made to any profile connected with the old X. That would limit its utility significantly.

So, as I see it: lots of work to program and test, little real benefit.

There are plenty of things on the priority list where it's the other way around.

Chris

P.S. For others' reference: http://www.wikitree.com/wiki/Merging#Accidental_merges

Comments

Chris,

I have some experience at databases, and understand that a simple undo button would be very complicated to implement. What I had in mind was more to have a snapshot of the profiles that existed before the merge (say Richardson-1577A), so that it would be easier to reconstruct the prior conditions. These relicts could expire after a month or so. A terabyte here and there of storage is not that big a deal anymore.

Looking at the example I provided you can see that it is indeed a mess, and will involve probably the best part of a day to undo, so I must respectfully disagree with you that there is little benefit.

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Toby -

Fellow sysadmin/developer/DBA here.  I've been on the receiving end of bad merges that needed to be undone before and certainly understand your frustration, but the effects of an "undo" feature could be far-reaching.

I think everyone agrees that successive edits and merges after the "snapshot" would be affected by a rollback, but the big issue that I can see is that since profiles are part of a singular (well, one day maybe) collaborative tree, many users could be potentially affected.  You may have one of your ancestors merged by another user and then later "un-merged" only to have subsequent edits by yourself and others just disappear into the ether.  Granted, as IT folks, we know that there are ways to keep them from just being tossed, but I would imagine that the majority of the user base would be fairly alarmed if this scenario were played out, regardless of how the back-end system is designed.  

Sure, something could probably be designed to accomplish this and not offend the sensibilities of most users, but is it worth the ROI?  This would surely take a lot of time to develop, but how many accidental merges actually take place in a given period of time?

-Allen

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Doesn't the "Changes" tab serve pretty much the same function as a "snapshot"? I know that I've been able to go in there and retrieve information that was lost during a merge.

Just a thought.

Krissi

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Thanks, Allen and Krissi.

I think the best next step would be to make the changes pages ("diff" pages) easier to interpret and use.

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Krissi -

Sorry for using geek terminology! :)  A snapshot is a point in time, almost like hitting "undo" in a word processor.  The Changes tab is a lifesaver for trying to manually undo a merge by hand keying the information, but a snapshot in this context would be like hitting an undo button to make everything "automagically" go back to the way it was pre-merge.  There's a lot of stuff that has to take place under the hood to make something like that happen.

-Allen

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Allen,

Thanks for clarifying, and for teaching me something new today! That makes total sense the way you explained it.

p.s. I like the word "automagically".

Krissi

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Almost three years, no apparent progress.  As to the Changes button. it brings up the text of the biography, but I haven't seen the text of the upper portion, the birth and death dates and places, the names, etc. Once merged those seem to be gone.