我已经使用Subversion很多年了,在使用SourceSafe之后,我爱上了Subversion。结合TortoiseSVN,我真的无法想象它还能有什么更好的。
然而,越来越多的开发人员声称Subversion存在问题,我们应该转向新的分布式版本控制系统,比如Git。
Git如何改进Subversion?
我已经使用Subversion很多年了,在使用SourceSafe之后,我爱上了Subversion。结合TortoiseSVN,我真的无法想象它还能有什么更好的。
然而,越来越多的开发人员声称Subversion存在问题,我们应该转向新的分布式版本控制系统,比如Git。
Git如何改进Subversion?
当前回答
SubVersion最让我恼火的一点是它把自己的文件夹放在项目的每个目录中,而git只把一个文件夹放在根目录中。这不是什么大事,但这样的小事积少成多。
当然,SubVersion有Tortoise,它(通常)非常好。
其他回答
“为什么Git比X好”概述了Git相对于其他scm的各种优缺点。
简要:
Git tracks content rather than files Branches are lightweight and merging is easy, and I mean really easy. It's distributed, basically every repository is a branch. It's much easier to develop concurrently and collaboratively than with Subversion, in my opinion. It also makes offline development possible. It doesn't impose any workflow, as seen on the above linked website, there are many workflows possible with Git. A Subversion-style workflow is easily mimicked. Git repositories are much smaller in file size than Subversion repositories. There's only one ".git" directory, as opposed to dozens of ".svn" repositories (note Subversion 1.7 and higher now uses a single directory like Git.) The staging area is awesome, it allows you to see the changes you will commit, commit partial changes and do various other stuff. Stashing is invaluable when you do "chaotic" development, or simply want to fix a bug while you're still working on something else (on a different branch). You can rewrite history, which is great for preparing patch sets and fixing your mistakes (before you publish the commits) … and a lot more.
有一些缺点:
There aren't many good GUIs for it yet. It's new and Subversion has been around for a lot longer, so this is natural as there are a few interfaces in development. Some good ones include TortoiseGit and GitHub for Mac. Partial checkouts/clones of repositories are not possible at the moment (I read that it's in development). However, there is submodule support. Git 1.7+ supports sparse checkouts. It might be harder to learn, even though I did not find this to be the case (about a year ago). Git has recently improved its interface and is quite user friendly.
在最简单的用法中,Subversion和Git是差不多的。两者之间没有太大区别:
svn checkout svn://foo.com/bar bar
cd bar
# edit
svn commit -m "foo"
and
git clone git@github.com:foo/bar.git
cd bar
# edit
git commit -a -m "foo"
git push
Git真正的亮点在于分支和与其他人一起工作。
我最近一直住在Git的土地上,我喜欢用它来做个人项目,但是我还不能把工作项目从Subversion转换到Git上,因为它改变了工作人员的想法,而且没有紧迫的好处。此外,我们内部运行的最大项目非常依赖于svn:externals,从我目前所看到的来看,它在Git中并不能很好地无缝工作。
SubVersion最让我恼火的一点是它把自己的文件夹放在项目的每个目录中,而git只把一个文件夹放在根目录中。这不是什么大事,但这样的小事积少成多。
当然,SubVersion有Tortoise,它(通常)非常好。
This is the wrong question to be asking. It's all too easy to focus on git's warts and formulate an argument about why subversion is ostensibly better, at least for some use cases. The fact that git was originally designed as a low-level version control construction set and has a baroque linux-developer-oriented interface makes it easier for the holy wars to gain traction and perceived legitimacy. Git proponents bang the drum with millions of workflow advantages, which svn guys proclaim unnecessary. Pretty soon the whole debate is framed as centralized vs distributed, which serves the interests of the enterprise svn tool community. These companies, which typically put out the most convincing articles about subversion's superiority in the enterprise, are dependent on the perceived insecurity of git and the enterprise-readiness of svn for the long-term success of their products.
但问题是:Subversion是架构的死胡同。
Whereas you can take git and build a centralized subversion replacement quite easily, despite being around for more than twice as long svn has never been able to get even basic merge-tracking working anywhere near as well as it does in git. One basic reason for this is the design decision to make branches the same as directories. I don't know why they went this way originally, it certainly makes partial checkouts very simple. Unfortunately it also makes it impossible to track history properly. Now obviously you are supposed to use subversion repository layout conventions to separate branches from regular directories, and svn uses some heuristics to make things work for the daily use cases. But all this is just papering over a very poor and limiting low-level design decision. Being able to a do a repository-wise diff (rather than directory-wise diff) is basic and critical functionality for a version control system, and greatly simplifies the internals, making it possible to build smarter and useful features on top of it. You can see in the amount of effort that has been put into extending subversion, and yet how far behind it is from the current crop of modern VCSes in terms of fundamental operations like merge resolution.
现在,对于那些仍然相信Subversion在可预见的未来足够优秀的人,我有一个发自内心的不可知论的建议:
Subversion永远不会赶上从RCS和CVS的错误中吸取教训的新型vcs;这在技术上是不可能的,除非他们从头开始重新配置存储库模型,但这样就不是真正的SVN了,不是吗?不管你认为自己有多不具备现代VCS的能力,你的无知也无法保护你远离Subversion的陷阱,其中许多情况在其他系统中是不可能或很容易解决的。
It is extremely rare that the technical inferiority of a solution is so clear-cut as it is with svn, certainly I would never state such an opinion about win-vs-linux or emacs-vs-vi, but in this case it is so clearcut, and source control is such a fundamental tool in the developer's arsenal, that I feel it must be stated unequivocally. Regardless of the requirement to use svn for organizational reasons, I implore all svn users not to let their logical mind construct a false belief that more modern VCSes are only useful for large open-source projects. Regardless of the nature of your development work, if you are a programmer, you will be a more effective programmer if you learn how to use better-designed VCSes, whether it be Git, Mercurial, Darcs, or many others.
Subversion非常容易使用。在过去的几年里,我从来没有发现任何问题或事情没有像预期的那样工作。此外,还有许多优秀的GUI工具,对SVN集成的支持也很大。
With Git you get a more flexible VCS. You can use it the same way like SVN with a remote repository where you commit all changes. But you can also use it mostly offline and only push the changes from time to time to the remote repository. But Git is more complex and has a steeper learning curve. I found myself in the first time committing to wrong branches, creating branches indirectly or get error messages with not much informations about the mistake and where I must search with Google to get better informations. Some easy things like substitution of markers ($Id$) doesn't work but GIT has a very flexible filtering and hook mechanism to merge own scripts and so you get all things you need and more but it needs more time and reading of the documentation ;)
如果您主要脱机使用本地存储库,那么如果本地机器上丢失了某些东西,则没有备份。使用SVN,您主要使用远程存储库,同时您的备份也在另一个服务器上… Git也可以以同样的方式工作,但这并不是Linus的主要目标,要有类似SVN2的东西。它是为Linux内核开发人员和分布式版本控制系统的需要而设计的。
Git比SVN好吗?只需要一些版本历史记录和备份机制的开发人员可以轻松地使用SVN。经常使用分支、同时测试更多版本或主要离线工作的开发人员可以从Git的特性中受益。有一些非常有用的特性,比如SVN中没有的存储特性,可以使工作更轻松。但另一方面,并非所有人都需要所有功能。所以我看不到SVN的死角。
Git需要一些更好的文档,错误报告必须更有帮助。而且现有的有用的gui也很少。这次我只找到了一个支持大多数Git特性的Linux GUI (Git -cola)。Eclipse集成正在工作,但还没有正式发布,也没有官方更新站点(只有一些外部更新站点,从主干定期构建http://www.jgit.org/updates) 因此,现在使用Git的首选方式是命令行。