adocentyn/50-git-questions

50 Frequently Asked question about Git & GitHub

50 Git questions (with answers)

A list of 50 frequently git questions with answers. Released under a CC-BY 4.0 license.

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1. How to check if git is available on your system?

$ git --version

2. How to initialize a new Git repository?

$ git init project
$ cd project

3. How to tell git about your name and email?

$ git config --global user.name "<your name>"
$ git config --global user.email "<your email>"

4. How to tell git to not use vi as the default editor?

$ git config --global core.editor "nano -w"

5. What is the staging area?

The staging area is an intermediate storage for changes that will be part of the next commit.

6. How to add a file to the staging area?

$ git add <file>

7. How to remove a file from the staging area?

$ git reset HEAD -- <file>

8. How to make a commit?

$ git commit -m "Commit message"

9. Where are git preferences saved?

$ git config --list --show-origin

10. How to ignore untracked files?

Add them to a local .gitignore file

11. How to untrack a file without deleting it?

$ git rm --cached <file>

12. How to undo the most recent commit?

$ git reset HEAD~
$ nano <file>
$ git add <file>
$ git commit -c ORIG_HEAD

13. How to change the message of the last commit?

$ git commit --amend -m "New message"

14. How to add a remote repository?

$ git remote add <name> <url>

15. How to compare a file to the last committed version?

$ git diff HEAD -- <file>

16. How to rename a remote?

$ git remote rename <old_name> <new_name>

17. How to change the address of a remote?

$ git remote set-url <name> <new_url>

18. How to send your changes to a remote repository?

$ git push

19. How to synchronize your local and remote repositories?

20. What is the different between reset and revert?

21. How to tell git to ignore trailing whitespaces?

22. What is the difference between git add *; git commit and git commit -a -m?

23. What is the difference between pull and fetch?

24. How to make a commit from another author?

$ git commit --author "Name Surname <email@address>" ...

25. How to create a branch?

$ git branch BRANCHNAME

26. How to switch to a branch?

$ git checkout BRANCHNAME

Tip:

$ git checkout -b BRANCHNAME

Will create and switch to the branch called BRANCHNAME

27. How to know when a file was first added to the repository?

28. How to get a list of all deleted files?

29. How to completely remove (sensitive) files from history?

You can't unless you change the history

30. How to list remote repositories?

$ git remote -v

31. How to tag a specific commit?

$ git tag -m '...' <commit>

32. How to get a list of tags?

$ git tag

33. How to merge 3 last commits into a single one?

34. How to get last modification for a given file?

35. How to swap branch master with another one?

36. How to access all commits in case of problem?

37. How to get all the commits from a specific user?

38. How to ignore the .gitignore file?

In the global gitignore add a line like this

.gitignore

Or in the root of a dir add a line like this

folder_where_is_its_gitignore/.gitignore

39. How to get the list of unpushed commits?

$ git log @{u}..

40. How to compare a file across two different branches?

$ git diff <branch-a> <branch-b> -- <file>

41. How to merge two git repositories?

A single branch of another repository can be easily placed under a subdirectory retaining its history. For example:

git subtree add --prefix=rails git://github.com/rails/rails.git master

42. What is the difference between HEAD and ORIG_HEAD?

43. How to use a global .gitignore?

Create ~/.config/git/ignore with a list of patterns.

44. What if the difference between rm and git rm?

git-rm - Remove files from the working tree and from the index rm - remove files or directories

45. How prevent a push if remote has extra commits?

This is the default with git push, not necessary to do anything.

You need to do that in the remote

46. How to create a git alias command?

$ git config --global alias.THEALIASED "WHAT_GIT_COMMAND_TO_ALIAS"

Note: If you want to alias a real command not a git command you need to use ! but your shell will try to find an event so you need to use a "!echo 'Test'"

47. How to undo a pushed commit?

Some blog post on freecodecamp

Briefly :

git fetch is the command that tells your local git to retrieve the latest meta-data info from the original (yet doesn’t do any file transferring. It’s more like just checking to see if there are any changes available).

git pull on the other hand does that AND brings (copy) those changes from the remote repository.

48. How to find the first commit?

git log master HEAD~ --oneline | tail -1 | awk '{ print $1 }'

49. How to find top contributor?

git shortlog -s -n | head -1

If you remove | head -1 you get all contributors

50.