git flow clarification - is rebase better than merge? Please explain

Question

When working with git, before starting work on a feature or an issue, I would do following steps

git checkout master // make sure you are on local master

git fetch origin // get latest commits from remote

git merge origin/master // merge latest commits from remote into local master

git checkout -b new-branch // create new branch from up-to-date remote master

However, I am reading Atlassian tutorial for feature-branch workflow, and they suggest doing following

git checkout master

git fetch origin

git reset --hard origin/master

git checkout -b new-branch

Obviously, except step 3, we follow identical steps. But as new git user, I am confused with step 3 even after I read explanation of what it does.

What is different btw my and their step 3? Which and why is better?

Answer 1

The example you show is from Atlassian's Git Feature Branch Workflow Under normal circumstances, after a fetch, there is not difference between git merge origin/master and git reset --hard origin/master.

However, reset --hard is destructive and I would avoid executing it routinely. merge is something you could undo if you execute it by accident in a wrong branch, or at a different moment.

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Simpler way

BTW, you can just

git checkout master
git pull 
git checkout -b feature_branch

Answer 2

Have a look into this post

Briefly:
- git merge apply all unique commits from branch A into branch B in one commit with final result
- git merge doesn’t rewrite commit history, just adds one new commit
- git rebase gets all unique commits from both branches and applies them one by one
- git rebase rewrites commit history but doesn’t create extra commit for merging

Answer 3

Your question is a bit wrong!

git reset --hard origin/master

is not rebase, it's hard reset; see also Reset Demystified.

In your case it means "remove all local changes in the current branch and move the branch pointer to origin/master". The advantage of it is the command completely synchronizes your local branch with remote; the disadvantage is that it removes your local commits and uncommitted changes if there were any.