[Git] Git Log and Undo Commit

♠ Posted by NN TRUNG at 18:14

One thing you will quite often do in Git if that team work is to check those who commit to the project you are working on, and how you undo previous commit if you feel the lack of a collective certain information in advance commit to supplement.

See git log

To view a history of previous commits, you use the command git log is to be found.

  $ Git log
 commit 3f1ef84ada3dfd936735d8724f9bbb3437c77b19
 Author: Thach Pham <contact@thachpham.com>
 Date: Tue 21 Apr 2015 17:16:37 -0700

  Hihi

 commit 6e729a49a36b31919daa6263f8f98f3a59d5bab3
 Author: Thach Pham <contact@thachpham.com>
 Date: Tue 21 Apr 2015 14:47:47 -0700

  First commit on Github 

You see? Every commit has a separate checksum, and it can also indicate who commit to and commit to how much day, any time.

Also, you can add the parameter -p to show details of a commit.

  $ Git log -p
 commit 3f1ef84ada3dfd936735d8724f9bbb3437c77b19
 Author: Thach Pham <contact@thachpham.com>
 Date: Tue 21 Apr 2015 17:16:37 -0700

  Hihi

 diff --git a / README.md b / README.md
 db7e814..e08f24f index 100644
 --- A / README.md
 +++ B / README.md
 @@@@-1 +1
 - # Git co Huong dan ban
 + Hhih \ n
 diff --git a / faq.html b / faq.html
 100644 new mode file
 Index 0000000..e69de29

 commit 6e729a49a36b31919daa6263f8f98f3a59d5bab3
 Author: Thach Pham <contact@thachpham.com>
 Date: Tue 21 Apr 2015 14:47:47 -0700

  First commit on Github

 diff --git a / README.md b / README.md
 100644 new mode file
 Index 0000000..db7e814
 --- / Dev / null
 +++ B / README.md
 @@@@-0.0 +1
 + # Git co Huong dan ban 

Note: If the log is too long, use the up and down arrow keys to read and press Ctrl + Z to exit.

Or if you'd just like to see the most recent commit is one more parameter -1 in.

You also could use some additional options for optimal viewing logs after the process than reading log.

• --since , --after : See the commits since a certain date.
• --until : See the previous commit certain date.
• --author : See the commit of someone.
• --grep : Filtering the strings in the log and printed.

For example:

  $ Git log --author=contact@thachpham.com --pretty = "% s"
 Hihi
 First commit on Github 

Cai --pretty is what I will say below.

Filter log with --pretty

Parameters --pretty very useful if you want to filter certain whether an object in the commit history, like only see messages commit or just watch people commit mail.

Using parameters --pretty you must write its tag attached the following:

  $ Git log --pretty = "% tag" 

The %tag must be placed in quotation marks, and you can use multiple %tag differently.

List of %tag :

• %H - Commit hash
• %h - abbreviated commit hash
• %T - Tree hash
• %t - abbreviated hash tree
• %P - Parent hashes
• %p - abbreviated parent hashes
• %an - Author name
• %ae - Author e-mail
• %ad - Author date (format respects the -date = option)
• %ar - Author date, relative
• %cn - committer name
• %ce - committer email
• %cd - committer date
• %cr - committer date, relative
• %s - Subject

For example:

  $ Git log --pretty = "% secure -% s"
 Thach Pham - Hihi
 Thach Pham - First commit on Github 

More tips see beautiful log

You can see when typing git log parameters without accompanying it appeared difficult to see. But there is one way you can do neat the default log, and add color to it so you look better.

First you copy this command to set.

  git config --global alias.lg "--color --graph log --pretty = format:"% h% Creset Cred% -% C (yellow)% d% s% Cgreen Creset% (% cr)% C ( bold blue) <% Security>% Creset '--abbrev-commit " 

Now to see the log, you just need to type git lg to see. You can combine it with the parameters above.The most important thing is with this view, you can see the HEAD (pointer of current branch) that later when you learn to branch you will find it very useful.

Undo Commit

If you need to remove the previous commit and needed to commit to undo, you can use the parameter--amend in command git commit .

  $ Git log --pretty = "% s"
 Hihi
 First commit on Github
 $ Git commit -m --amend "Hehe"
 [Master 3682e56] Hehe
  Date: Tue 21 Apr 2015 17:16:37 -0700
  2 files changed, 1 insertion (+), 1 deletion (-)
  create mode 100644 faq.html
 $ Git log --pretty = "% s"
 Hehe
 First commit on Github 

Note that undo means you commit step back last time, so if you need any additional files to commit, please put that file in front Staging Area.

Skip files from Staging Area

If you've put a certain file in Staging Area but now you want to remove it from here to not commit so it could be used commands git reset HEAD tên_file . What is the next HEAD section branching (Branch) I'll explain.

Epilogue

In this article you learned how to manipulate to review the history of commits to track better commits, and how you restore operation involves Commit. However, you can see that I have said over the management of the Git version yet? Never, right? Okay, so in the following article I will guide you to become familiar with the features Tagging (tick) of Git and this is how we manage each version of code.