Upload Files

cd path/to/store/clone/files
git clone https://github.com/~/~

cd local/repository/path
git add .
git commit -m 'Add a new file'
git push origin main

Create a git repository

First, create a folder and use git init. pwd will show the path of folder mytest

mkdir mytest
cd mytest 
pwd
git init

Then, create a .txt file, add and commit the file

git add readme.txt
git commit -m "create a new file"

Version Tracking

Show the commit history. use git log or git log --pretty=oneline are both ok.

git log

I can go back to a previous version. HEAD is current version, and it can be replaced by commit_id. Use git reflog to check commit id.

git reset --hard HEAD

Working directory, Staging area, Master

Using git status to check working directory and staging directory.

Withdraw

Withdraw all changed made in working directory by using git checkout -- file_name. This command in deed uses file_name in git repository to replace the file in working directory.

Withdraw all changed made in staging directory by using git restore --staged file_name, and then using above line to withdraw working directory changes.

Delete

Delete a file in git repository.

git rm file_name
git commit -m "delete file file_name"

If I use git rm file_name, the file will be deleted in working directory and the file’s deleting status will be sent to staging directory. The process keeps the same when I delete a file in Windows Explorer.

Create a ssh key

Create a ssh key for a computer:

ssh-keygen -t rsa -C "youremail@example.com"

Then open github account setting to add a new ssh key from local user file .ssh/id_rsa.pub. After doing this, the computer can push git repository to github repository.

Link a remote repository

Below shows how to link a github repository through ssh. origin is default repository name, and git@server-name:path/repo-name.git is repository link.

git remote add origin git@server-name:path/repo-name.git

Push

Push my local repository at the first time.

git push -u origin master 

Push my local repository afterwards.

git push origin master 

Branch

Create a branch named “dev”, and switch to the “dev” branch:

git checkout -b dev
## git switch -c dev

Or I can use git branch dev to create a branch and use git checkout dev to switch to the branch.

Use git branch to show all local branches. The branch with * is the current branch.

Use git branch -r to show all remote branches, which begin with “origin/”.

Use git branch -a to show all local and remote branches.

Using the code below to merge specified branch with the current branch:

git merge specified_branch_name

Using the code below to delete a branch:

git branch -d specified_branch_name

If I want to delete an unmerged branch, I need to use -D instead.

Conflict

When I try to merge two conflictive branches, the merge process will fail, and turn into the merging status. At this status, I can open the conflictive files and correct them. After that, I can use git add . and git commit -m " " to complete merging.

Collaboration

When clone from a github repository, I can’t see other branches. I must use git checkout -b dev origin/dev to create a branch connecting to the dev branch.

If there is conflict when I push to remote repository, I can use git pull origin branch_name to clone and merge locally. After slove the conflict problem locally, I can push the branch_name to remote repository.