Git MERGE vs REBASE: Everything You Need to Know
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- čas přidán 9. 08. 2023
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2 minutes into the video and animations help understand rebase 1000x better than any static explanation on any website ever could.
Thank you.
this is what you see happening when using a gui like fork
@@z0nx Using GUI help to understand the process much better. I agree.
So well put.
Yes, great video!
Git rebase rewrite history and rewrite history is evil
My workflow
1. Create a feature branch.
2. Keep pulling and rebasing the changes from the main branch cmd : git pull -- rebase
3. Once done with my features, squash all commit to one
4. Merge the features branch into main
This is the best way
whoever does not do this, you have serious mental issues
One of the best channels to learn about sw technologies. No fluff talks, no distracting music, no ads, pure substance with straight to the point explanations and amazing animation!
And in an infectiously peaceful way. Amazing!
I really want to know how they do all their animations!
There's a reason merging squash commits is so popular, and that's because it's the easiest and most compatible with how most people use git. Most people want their branch to be their own workspace, and while in some kind of fantasy world each commit would be filled with very useful information, in reality it's mostly swear words and short notes. Having squash commits and PRs can force developers to write a longer, better description of their entire feature when merging instead, and get rid of all the mostly scattered and hard to understand commits from the feature branch. The only people I've ever met that prefer rebasing are people who live and breathe git and feel like every commit is sacred, but this is an incredibly tedious way to work -- if your features are so large that you feel that the history of a hundred commits is necessary, just make smaller features, or better yet, actually comment your code like you're supposed to.
This is exactly why looked up this video, I have weird commit messages and some commits that I don't want to appear in the main history (fixing typos for example).
@@kinkajou2310 interactive rebasing is a great use case for squashing your own commits, but when following the process I just described it also doesn't matter much since *all* commits will disappear when the feature branch is merged into "dev" or whatever anyway. There are obviously use cases for not using merge commits ("release merges" from dev -> main are one of them), but rebases are also inherently more dangerous since they, unlike merging, can lead to losing your history completely if you're sloppy when resolving merge conflicts.
Instead of writing swear words and short notes before making a PR one could split up their work into meaningful chunks by soft-resetting their branch and staging important bits of code into their own meaningful parts. Or better yet, start by doing exactly that at the very beginning of the feature development. For example.
• Task#69: Implemented tests for feature whatever
|
• Task#69: Implemented admin tools to control feature whatever
|
• Task#69: Implemented main business logic for feature whatever ## (this is where the soft-reset probably happened)
|
• Task#69: Refactored some stuff to make implementeation of feature whatever less painful/more better etc ## (the actual start of feature development)
It's your own branch, you can make it as pretty as you want it. And others can appreciate all the logically split bits instead of trying to makes sense of all the "wip", "some shit i did here" and "bubble sort or something, idk, i'm not a programmer" commits during code review.
It's always faster to review individual commits when they make sense instead of staring at the wall of code. At least for me
P.S. I'm rebase and fastforward guy all the way btw. But you gotta clean up your commits first. Even if you'll squash them into one
The best explanation I found.
Sounds like a skillissue to me. Clear comitts and comments are an essential part of documentation.
Tried various strategies and so far I prefer to always work with merge commits and almost no rebase (unless the branch was never published).
Merge from main branch to feature branch.
Merge from feature branches to master when ready, no squash, no fast forward, always creating a merge commit.
I don't find the history messy as it's exactly as development happened.
Remember that you can always see history with --first-parent if you want to see only a commit (similar with how squash result can be viewed).
I've read (and experienced) that reabase can actually create havoc when other people have the branch on their machines. It is the most attractive solution though because it makes reviews easy. You don't see noise from the parent branch on your feature branch. Its too bad that Git's implementation allows for this attractive intuitive feature to be risky.
Believe me, you always make us clear long due complex topics in a single shot. I have been trying to figure out this topic for the past few years, but never understood. Thanks a lot! We ❤ your channel.
I've never used rebase and squash techniques but i like the way they combine the commits in the feature branches to the main branch. Thank you ❤
We *squash* our personal PRs and *merge* our team branch to main. To update my branches I prefer *rebase* . But rebase is not so good if several people work on the same branch.
Git rebase is very safe. It's like Russian Roulette -- you have a significantly greater than 80% chance of surviving.
Our team follows the same plus when we need to sync main into other feature branches we use merge fast forward
One time I had to work with 1 or 2 other people in the same branch, because that's what we deploy to staging to test our features. It's quite messy, and when I want to deploy my changes, there were some conflicts, so I decided to rebase the staging branch from my feature branch because somehow the resolution is simpler, and force push it to staging. All good. Then after some time, my teammate asked me: "hey, did you delete my changes?". Turns out my local branch was outdated.
So yeah, don't rebase a shared branch. Or probably, don't force push a shared branch, which is what you'd need to do when rebasing
@@dale3478 Yes, if you work on the branch alone, then rebasing is the best option I think. Very clean.
But if someone else also works on the same branch things become more complicated. You should be very careful with impact on others. And Pull, Pull, Pull 😁
I don't understand. If you squash before rebase to main, what is the problem?
These animations really facilitate the meaning of these concept in a clear and concise manner. Thank you.
Wow. I've watched some of your videos and they are MASTERPIECES. You put a lot of work into these videos and it's great! Keep up the great work!
One major advantage of using rebase instead of merge that is not mentioned in the video: when two developers work on different feature branches in parallel, when merging git will mix up the commits of each branch, so it's easy to break someone else's code. As an example, dev1 makes commit A at 9am and commit B at 11am, while dev2 makes a commit in a different branch at 10am. When merging both features, git tries to combine the 3 commits in this order: A, C, B. This mix up makes it easy to break code and merge conflicts become a mess. With rebase&fast-forward, the commits will be seen as A, B, C (or C, A, B if dev2 made the PR first). Just because the changes from both branches were committed in parallel, it does not mean that the logic in the code evolution follows the same logic, as the features were independently developed.
Hope that was clear enough - I feel like I didn't explain myself that well :')
To the creators: Great video! Could I suggest making an explanatory video on how to work with forks as a follow-up? I've been recently taught this together with rebase+squash by a senior dev & it has made my workflow so much better!!!
The explanation is perfect. And thanks for adding this to the conversation.
"when merging both features" - hopefully you're not actually talking about merging 2 feature branches into a main branch with 1 command, which is referred to as an "octopus" merge. I'm going to assume you're not, because in your rebase example you talk about whoever made the PR first. Confusing comment, because there is never a case where a conflict is handled any different in a merge vs a rebase - unless you're referring to an "octopus" merge which should never be done anyways (and isn't if pull requests are being utilized).
Yes whoever made a PR first their commits will be merged first
I think it won't matter who merges their branch to main branch as the commits will rewritten according to the timeline (In case of rebase). In above case A'->C'->B' as C was commited before B but in case of merge it's gonna be A-C-B--. Correct me if you think otherwise.
So in your example if we do git log after merge, it will show commits in this order :B, C, A?
Very nice video, short and insightful!
Thank you for reminding us that as anything in IT (and in life really), choosing a Git strategy is about pros and cons, and is specific to a given context.
No strategy is better than another, there just tools for teams to use, to get the job done.
Have a nice day!
Sir, your videos are just perfect. Keep the good work up, cant have enough of it.
This is amazingly simple and precise explanation. Thank you Sahn Lam.
I love your channel sooooo much .... Thanks a lot with my all grateful. Your video untied the huge knot in my brain .... thanks again! I will always be your big fan!
This guy graphics is always the best to understand and remember , thanks man !!
Alex, you truly are the epitome of excellence. With my 15 YOU as a SWE, I can confidently say that collaborating with someone of your calibre has undoubtedly been the utmost highlight in my professional journey.
He's not Alex though
Wow thanks! Really clear/clean/concise explanation!
This is the best video to explain it, clean and clear.
By far the best explanation I've seen on this topic
clear and straight to the point explanation and animations made concept very much easier to understand.. Thanks ! and subscribed !!!!!!
This is a great visual summary of each. I was always skeptical of using rebase and always merged with local commits before pushing my changes. But I think I like rebase conceptually better, I might start getting into the habit of using rebase in the future.
Amazing tutorial on rebase and squash. I loved the animation which gives you the exact operation of each right in front of your eyes. My gratitude to you for explaining all that.
much appreciated my dear friend !!
Thank you for your video. You gave a very clear and nice graphics and explanation. Awesome!
Excellent video - this is the best explanation of this I've seen
Updating my main branch, I prefer working with GIT MERGE. It feels a lot more straightforward for me more importantly is the fact that I can track my commit history when I make use of the MERGE option.
Thanks for this. It explained the details of these three features exquisitely.
The animation visualisation is great!!!
I love to update my branches and the merge them to master using squash haha. I love this channel. my new favourite of this year haha❤
The squash approach makes sense to me, you can see the whole change at once and the full detail in the branch if needed
It creates new hash though
@@prathameshbhat9816Thats great imo, you can easily cherry pick a squashed commit
@@prathameshbhat9816 why is that an issue?
@@Backtrack3332 reverse merges from prod to testing environment
If you use sub modules it can screw up some build dependencies
Very details! Thanks so much for helping the community understand more. I usually use Squash Commit to add the featured branch to the main after testing the new component on the featured brand.
I prefer the hybrid approach. First create a new feature branch from main branch. Add a few commits on feature branch. If the commits all belong to the same task or represent the same feature, fixup/squash them. If each commit represents distinct functionality or it makes sense to revert a part of the feature, not the whole feature, then don't use fixup/squash. After the work is done - rebase the branch with the main. Using this technique, you can combine both squash/rebase as needed.
Thank you so much!!! Subscribing faster than I ever have for any channel
With Git rebase, I find myself rebasing more often on the main branch in order to prevent the branch from diverging to much. It has the benefit of avoiding too many conflicts on the final rebase.
Dude you rules, I like all your videos! Thank you for your input )
The flowchart at 04:10 is brilliant.
This channel absolutely rocks.. ROCKS!
Thank you, for covering the topic that always gives me little anxiety while executing those commands 😃
I used to rebase the main branch into my feature branch. the issue with that which not many talk about is that if you're too many commits behind you'll be forced to fix merge conflicts on a commit by commit basis. i usually prefer merging now and then user interactive rebase to pick commits in my feature branch before pushing to main
that's why you do not need to have too many commints on your feature branch, squash them to one or two at most
Ah, The Great Debate. I’ve hunkered around many a whiteboard and heard endless iterations of passionate arguments for all approaches. Regardless of what you personally prefer, it all comes down to the project, your team, and what works for everyone. There’s no hard and fast rule and all approaches have their merit.
Best explanation so far. thanks
good job bbg! nice and simple explanation.. ill certainly check your other work
Love your content, cool graphics to help understand.
Absolutely love the visual way that you taught this, it's crystal clear. Thank you!
This guys explanation wasn't too bad, I guess. Thank you!
Your animations are the best!
I am just stunned by your animation 🤯
Amazing video. Thank you!
Such incredible animations!~
Nicely explained. I wanted something easy to recall, you know how it is. You forget after a few weeks!
This is a great reference to keep around.
Thanks! 👍🏻
great pictorial explanation.. Kudos to the Idea...
Thank you
very nice and clear, voice also very clear, thanks!
thank you. i learned something new today
beautiful video, thanks!
Excellent explanation!
Thank you for the clarification!
Simply AWESOME! ❤
This was more helpful than i can explain. I am collaborating on github for the first time and didnt know what any of the differences were and just had a terrible day merging changes when i should have rebased. Everything makes perfect sense now.
Right video at right time for me🔥
Exceptional video and explanation!
This is such a cool, useful and beautiful video
The best video on this topic🏆
Great video. Thank you
Rebase and merge ("semi-linear merge" - not fast forward!) is superior for cleaner change information. I call it the "knotted-rope".
After rebasing but before merging, I frequently reset soft and selectively commit the files in sets with messages that best describe what was done, in way that ensures each commit builds on the last. Sometimes it's necessary to commit partial file changes or even adjust the changes directly to better express a 'sub-commit'.
You can always compare the resulting refactoring with the original rebased branch head commit to confirm the sum total is the same, so there's no risk of losing changes with this approach.
What you end up with is clean, readable sets of delineated commits that are useful for future investigation into the history of changes - while still allowing the development process to be continuously committing to a branch without too much concern for the messages or presentation of the commits. It's a nice have your cake and eat it too approach
I can finally understand what rebase really does thanks man
Nicely explained ❤
I git merged all my life because rebase was scary from my knowledge of it, and i never knew about squash.
Now thanks to this video, rebase sounds like it makes sense now. Squash is the scary one because I could lose version history. But it's good to know that history will be preserved in the other branches.
The question is: How often to you look at the history of individual commits in a feature branch? I've learned that barely anyone does that. And even if some fatal flaw is found nobody looks back and tries to figure out what happened but instead it's usually fixed in yet another hotfix branch.
Rebasing looks good at first, but improperly done leads to a big headache due to the history being rewritten. Went through this and it's not a fun time. Squashing is actually the best of both worlds, you lose the fine detail of commits but it all gets merged into one commit and one big message. You can always see it afterwards, it's just harder to read. I only rebase local branches on the main one before I've done any commits on them, which is usually very early on after branch creation when a colleague merges a PR.
If your feature branches follow the single principle well the squash will make more sense after all.
I have the same view. We used to rebase at one point in the past but it was very problematic if there was an issue so we gave up (worked well if there were no problems). With merge, there is basically zero chance of screwing up the code base.
amazing explanation. thanks❤
This is very informative. Thank you
amazing explanation, thank you
Amazingly well animated video.
Great video. Thanks
Amazing channel man.
What a great video! Here is why I ask my team to avoid rebases and squashes. Sometimes I look back at the history for dead ends, i.e. commits with no descendants. Without rebases and squashes these generally fit one of three categories. (A) Work that later turned out not be needed, (B) work that is on-going and hasn’t yet gone into a merge request, and (C) work that should have gone into a merge-request, but didn’t. Hopefully the first category is rare. Rebase and squash create new commits and the older versions of those commits are left in the repository without descendents. That creates another category of commits without descendants: (D) useful work that was replicated elsewhere. It’s often hard to distinguish (D) from (B) and (C). Far from having a clean history, you have a messy history with a lot of dead ends and commits that replicate work on other commits. Well that’s how I see it, but I’m interested in reading the comments to see why others like rebasing and squashing.
I have used "git merge & squash" rebase sounds good. I'm gonna learn and do that. Thanks for explanation.
i've used merge only. Glad to learn about rebase!
Beautiful explanation
best youtube channel ever
Great explanation
Crystal clean explanation on the each values different models emphasize!
To better understand how to navigate potential challenges effectively, would it be possible for us to delve into depth of solutions and best practices aimed at mitigating the drawbacks associated with each approach with the exploring hypothetical worst-case scenarios? Looking forward to it.
I'm not a dev and I could follow the logic. Well presented! 🌟
you saved my day!
Rebase is rarely used now with CD, we make most commits on main, no feature branches.
Additionally, I’ve had plenty more merge problems when rebasing on to main.
Very rarely does anyone look at merge history, but we do use our merge history to generate release notes.
I'm probably doing it wrong, but there's two projects I work on and do it differently on each. One project is with a small team of 3 developers and we only merge. Commit history is not "messy" due to the size of the team and feature concurrency, but we get tonnes of detail which is helpful when tracking down regressions. My other project though, I use squash commits. Gitlab does a good job of building commit messages out of the feature commit history so I don't really lose anything. Main history is cleaner, etc.
best video on this topic !
For me rebasing works great in open source like enviornment, where Focus and review is on the changes contributed. In enviornment where many people work full time on a code base, the process is also part of what you need to track, so simple merges are both better and can avoid wrongly resolved conflicts - and you should build your linear history using different tool (like PR history).
We do this:
- Create a feature branch from main
- do works in feature branch
- and while doing PRs to main/dev, we squash commits into one and do PR.
- merge the PR to main/dev
This makes the commit history clean and we are really fan of it.
However, while doing this, we make sure that the team knows how git rebase works and how commit hash are changed when sqashing/rebasing so that we won't have to deal with weird commit hash mismatch issues.
Another thing that we widely use is the interactive mode of rebase. We use it from picking, rewording, squashing, editing, and fixing commits.
Great video!!!!!
main -> feature = rebase
feature -> main = squash + merge
rebase would be painful if the feature branch existed too long, you need to resolve conflicts from the oldest commit to the latest one(standard mode), squashing commits in the feature branch can improve the rebase experience, personally a better solution is to make a smaller task and PR.
I basically just use git merge, but I think I'll try git squash more as I sometimes have multiple branches feeding into main - thank you for this one.
All these fuss about rebase and a detailed and precise 5min video cleared that up for me. Thanks
10/10 thank you for this video!
Crystal clear ✨ 🔮
Wow very clear
thank you!
squash is my main go to at the moment. though from time to time I use the merge approach.
This CZcams tutorial excellently clarifies the Git dilemma between merge and rebase, offering concise insights for confident version control choices. A must-watch for mastering efficient collaboration and branch management.
Can you please share name of video editing software you're using. thanks
Great video. It's also good to note that git rebase is a form of rewriting history. This means that it should be used much more carefully when you work with other people on the same feature branch. Anyway, I personally used git merge + rebase with squash on main most often in many organizations..
I’m still yet to come across an issue using the rebase+squash strategy, so I really can’t see any reason not to use it. IMO a feature shouldn’t be picked apart after merge, just wholly reverted and fixed and remerged. Rarely could I revert a single commit from my feature branch (e.g. to resolve a bug after merge to main), and not have it break the feature entirely.
My approach
1. Have a default and master branch and both are protected branches and both the branches will always be in sync.
2. Create Feature branch for each feature from dev_master.
3. Merge all the features into dev_master
4. Merge dev_master into master
Thank you boss