Essential Git Tips and Commands After One Year of Use

After using Git for a year, I compiled a practical summary that covers most everyday scenarios and helps you work more efficiently.

Configure Git user name and email

git config --global user.name "xxx"
git config --global user.email "[email protected]"

View current configuration:

git config --list

Generate and use an SSH key

Check for an existing key: cd ~/.ssh If none exists, generate a new one: ssh-keygen -t rsa -C "[email protected]" Press Enter three times to accept defaults; you will obtain id_rsa and id_rsa.pub. Do not modify the keys after creation.

Change remote repository URL

git remote set-url origin [email protected]:res_dev_group/test.git
git remote -v

View file modification history

Show concise log for a file: git log --pretty=oneline <filename> Inspect a specific commit:

git show 356f6def9d3fb7f3b9032ff5aa4b9110d4cca87e

Fix push default warning

Git 1.x defaults to matching, while Git 2.x defaults to simple. To use the older behavior:

git config --global push.default matching

Use submodules for shared code

Add a submodule: git submodule add <repo_url> <path> Remove a submodule (edit .gitmodules then run): git rm --cached <submodule_path> Initialize submodules after cloning:

git submodule update --init --recursive

Cancel a staged file

git reset HEAD <file>...

Delete files

Remove from index and filesystem:

git rm file1
git commit

Remove only from index (keep in filesystem):

git rm --cached file1
git commit

Rollback to a previous commit

git reset --hard 248cba8e77231601d1189e3576dc096c8986ae51

Pull again if you need to revert the rollback.

Compare historical versions

git log
git show 4ebd4bbc3ed321d01484a4ed206f18ce2ebde5ca
git diff c0f28a2ec490236caa13dec0e8ea826583b49b7a 2e476412c34a63b213b735e5a6d90cd05b014c33

Branch management

git checkout -b new_branch
git branch
git checkout master
git merge new_branch
git branch -d new_branch

Resolve merge conflicts

Conflict markers look like:

a123
<<<<<<< HEAD
b789
=======
b45678910
>>>>>>> 6853e5ff961e684d3a6c02d4d06183b5ff330dcc
c

Keep your changes (between <<<<<<< HEAD and =======) and the incoming changes (between ======= and >>>>>>>), then commit.

Typical push failure and recovery

If git push fails because the remote has newer commits, first pull: git pull Resolve any conflicts, then repeat the usual workflow:

git add ...
git commit -m "..."
git push

Successful commit workflow

git status
git diff
git add dirname1/filename1.py dirname2/filenam2.py
git commit -m "fixed: modify upload logic"
git push

Understanding GitHub Pull Requests

Fork the original repository (Repo A) to your account (Repo A2), work on A2, then create a Pull Request on GitHub to ask the owner of Repo A to merge your changes.

Common error handling

Pathspec not found

git checkout master
git pull
git checkout new_branch

Large file push errors (HTTP 411/413)

Increase the HTTP post buffer size: git config http.postBuffer 524288000 If the error persists, ensure your SSH key is correctly added to the remote repository and retry the push.