Limit the depth of an SVN checkout

Version Control With Subversion, 2d Ed., p71

Sparse trees are useful when you only want to check out the contents of some branches, from the branches/ directory, but you don't want to change the structure of the repo. Just set the checkout depth of the branches you don't want, to empty. Then they'll remain empty in the working copy.

This only affects the working copy, not the repository itself. That is, this is only visible to you, and only affects your local machine.