With Subversion, for each project there is a single
repository at some detached central place where all
the history is and which you checkout and commit
Git works differently, each copy of the project tree
(we call that the working copy) carries its own
repository around (in the .git subdirectory in the
project tree root). So you can have local and remote
You can also have a so-called bare repository which is
not attached to a working copy; that is useful
especially when you want to publish your repository
In Subversion the URL identifies the location of
the repository and the path inside the
repository, so you organize the layout of the
repository and its meaning.
Normally you would have trunk/, branches/ and
In Git the URL is just the location of the
repository, and it always contains branches and
One of the branches is the default (normally
Subversion identifies revisions with ids of decimal
numbers growing monotonically which are typically
small (although they can get quickly to hundreds of
thousands for large projects). That is impractical in
distributed systems like Git.
Git identifies revisions with SHA1 ids, which are long
160-bit numbers written in hexadecimal. It may look
scary at first, but in practice it is not a big hurdle - you
can refer to the latest revision by HEAD, its parent as
HEAD^ and its parent as HEAD^^ = HEAD~2 (you can
go on adding carrets
Each commit has an author and a committer field,
which record who and when created the change and
who committed it
Git is designed to work well with patches coming by
mail - in that case, the author and the committer will
Git will try to guess your realname and email, but
especially with email it is likely to get it wrong. You
can check it using git config -l and set them with:
git config --global user.name "Your Name Comes Here"
git config --global user.email
The Git commands are in the form “git
Eg- “git commit …. “
You can interchangeably use the git-
command form as well
Eg “git-commit ….”
Git can produce colorful output for
Colors are disabled by default
Watch your repository using the gitk
repository viewer as you go.
Import your SVN repo into Git
• git svn clone https://svn.foo.com/svn/proj --trunk=trunk --branches=branches --tags=tags
Make your own Git branch
• git checkout -b work trunk
Add the files you changed
• git add <filename>
• git commit
Want to sync with master SVN?
• git svn dcommit
Why would we want this?
Since Git is a distributed revision control system
(while svn is a centralized one) you can perform
commits, brances and merges on your local working
When you want, you will be able to “push” your
changes back to the central SVN server
What are the advantages of this approach?
No downtime. Smooth migration
Existing system can run as-is while hooks are being
written to integrate git into the system.
• install git and git-svn
• create the working dir
• init your git working dir:
Init • cd <workdir> && git-svn init http://your_repo
• Find a commit regarding the project
Find • the command git-log will show project’s history starting from this revision
• Perform the command git-svn fetch –rREVISION
Fetch • Where REVISION is the number obtained before.
• Update your working dir: git-svn rebase
• You can commit your changes using git-svn dcommit
Sometimes, you may experience some problem when
synchronizing with the main development tree.
In fact you have to commit all local modifications (using the git-
commit command) before invoking git-svn rebase.
Sometimes it isn’t reasonable since your changes are not yet ready
to be committed.
git has a native solution also for this problem, just follow these
put aside your changes using the command: git-stash
update your working copy using: git-svn rebase as usual
take back your changes typing: git-stash apply
clear the stash by typing: git-stash clear
After the first step all your uncommitted changes will disappear
from the working copy, so you’ll be able to perform the rebase
command without problems.
For further informations read git-stash man page.
A DSCM gives a lot of flexibility when
development is happening across various
Care needs to be taken while doing an SVN
SVN & git should be used simultaneously
until the team is confident about git.
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