Undoing specific revisions in Subversion

Question

Suppose I have a set of commits in a repository folder...

123 (250 new files, 137 changed files, 14 deleted files)
122 (150 changed files)
121 (renamed folder)
120 (90 changed files)
119 (115 changed files, 14 deleted files, 12 added files)
118 (113 changed files)
117 (10 changed files)

I want to get a working copy that includes all changes from revision 117 onward but does NOT include the changes for revisions 118 and 120.

EDIT: To perhaps make the problem clearer, I want to undo the changes that were made in 118 and 120 while retaining all other changes. The folder contains thousands of files in hundreds of subfolders.

What is the best way to achieve this?

The answer, thanks to Bruno and Bert, is the command (in this case, for removing 120 after the full merge was performed)

svn merge -c -120 .

Note that the revision number must be specified with a leading minus. '-120' not '120'

Answer 1

To undo revisions 118 and 120:

svn up -r HEAD       # get latest revision
svn merge -c -120 .  # undo revision 120
svn merge -c -118 .  # undo revision 118
svn commit           # after solving problems (if any)

Also see the description in Undoing changes.

Note the minus in the -c -120 argument. The -c (or --change) switch is supported since Subversion 1.4, older versions can use -r 120:119.