Checking out from svn only if files are different

I already have about 80% of the files I need to checkout from SVN. But these files are not current;y under version control in my local system. Now I want to checkout a directory, but I want only the remaining 20% of the files to be downloaded. T开发者_高级运维he other files, which I already have, should only be validated against the repository, and downloaded only if they are different from the repository version. Is this possible?

As far as I can see, there is no supported method to do that. SVN wants to download a copy of each file into the .svn folder in the working copy. That copy is used for creating the diff of edited files.

It could be possible to manually edit the content of the .svn folder and create all necessary base files and index files but that will be a lot of manual work and there is no guaranteed way to make sure the repository is in sync afterwards.

Edit:
I can not figure out a way to modify the entries file with only some files and have svn fetch the others. Unless you are in serious trouble, the best option is to just check everything out from scratch.

The standard way to do this is to use a working copy, which it sounds like you do not have. You have something like a partial or sparse export. Essentially you are asking to "update" something that is not a working copy.

Without a working copy, I don't think there are any svn client tools that will help you do that. TortoiseSVN certainly won't.

If your SVN server is working over http, you might be able to use something like wget -m, but you'd have to get wget onto your machine first. And I think it uses timestamps to make the determination, so that may or may not be suitable in your case.

If it were me, I would just check out a fresh working copy. Once you have it you can just update it whenever you want. That's kind of the point.