Does "svn update" download everything or just the diff patches?

I need to know a bit about subversion internals. Anyone know 开发者_如何转开发why actually gets transferred during a svn update? Say I have a huge file in the repo, with just a few lines changed. Will svn update download the whole file or just the changes?

Thanks!

If you do a simple svn update you will get just the difference between your current REVISION and the HEAD revision on the server.

Only changes is correct.

Pablo is correct, plus it will also remove any stale locks. Suggest you read the friendly manual, it's very good.