Log - the Commit History

So, now we have all this history in our Git repository. So what? What can we do with it? How can we see this history?

The answer is the very powerful git log command. The log command can show you nearly anything you want to know about your commit history. Also, since the entire history is stored locally, it's really fast compared with most other SCM systems, especially if your repository is packed (see the "Care and Feeding" section).

If you just run git log, you will get output like this:

$ git log
commit cf25cc3bfb0ece7dc3609b8dc0cc4a1e19ffbcd4
Author: Scott Chacon <schacon@gmail.com>
Date:   Mon Mar 17 21:52:20 2008 -0700

    committing all changes

commit 0c8a9ec46029a4e92a428cb98c9693f09f69a3ff
Author: Scott Chacon <schacon@gmail.com>
Date:   Mon Mar 17 21:52:11 2008 -0700

    changed the verison number

commit 0576fac355dd17e39fd2671b010e36299f713b4d
Author: Scott Chacon <schacon@gmail.com>
Date:   Sat Mar 15 16:40:33 2008 -0700

    my second commit, which is better than the first

commit a11bef06a3f659402fe7563abf99ad00de2209e6
Author: Scott Chacon <schacon@gmail.com>
Date:   Sat Mar 15 10:31:28 2008 -0700

    first commit

This will show you the SHA-1 of each commit, the committer and date of the commit, and the full message, starting from the last commit on your current branch and going backward in reverse chronological order (so if there are multiple parents, it just squishes them together, interleaving the commits ordered by date)

Formatting Log Output

The default format takes up a lot of space though, so there are ways to limit and format this output differently. --pretty is a useful option for formatting the output in different ways.

For example, we can list the commit SHA-1s and the first line of the message with --pretty=oneline:

$ git log --pretty=oneline
cf25cc3bfb0ece7dc3609b8dc0c committing all changes
0c8a9ec46029a4e92a428cb98c9 changed the verison number
0576fac355dd17e39fd2671b010 my second commit, which is..
a11bef06a3f659402fe7563abf9 first commit

With --pretty, you can choose between oneline, short, medium, full, fuller, email, raw and format:(string), where (string) is a format you specify with variables (ex: --format:"%an added %h on %ar" will give you a bunch of lines like "Scott Chacon added f1cc9df 4 days ago").

Filtering Log Output

There are also a number of options for filtering the log output. You can specify the maximum number of commits you want to see with -n, you can limit the range of dates you want to see commits for with --since and --until, you can filter it on the author or committer, text in the commit message and more. Here is an example showing at most 30 commits between yesterday and a month ago by me :

git log -n 30 --since="1 month ago" --until=yesterday --author="schacon"

git log

Git Internals