Note:

If the user has updated all the files of specific directory without updating the directory itself its revision won't change. So as revision number is the SVN® property there might be some conflicts during setting of properties, so it's recommended to update the whole directory. Also there might br conflicts while deleting/adding files with the same names both in the working copy and repository one.

If there were some conflicts during the update operation cycle SVN® updates what it can and notify the user about the conflict. Then three file are created: 'name'.mine (copy of the user's local file before update), 'name'.BASEREV (copy of the base revision file) and 'name'.rNEWREV (copy of the repository revision file). So the edit conflicts action must be run to resolve conflicts.