All Directories that exist in the Directory table must have a Directory Parent that eventually resolves to TARGETDIR.

Each row in the Directory table has a Directory Parent.  if you concatanate each row for children and parent, you will get the path to the directory.

Example:

Directory                                      Directory Parent
ProgramMenuFolder                    StartMenuFolder
StartMenuFolder                          ProfilesFolder
ProfilesFolder                              WindowsFolder
WindowsFolder                           TARGETDIR

If you put these rows together you will get the path:

<Drive>:\Windows\Profiles\Start Menu\Program Files

NOTE:  TARGETDIR resolves to the drive letter for the installation (example C:\).  There will never be a Directory parent for TARGETDIR in the Directory table.  The Full Directory column was included in the Directory table to show the full path to a particular directory.  TARGETDIR could be different drives for different machines, so this column is not populated.  This is expected and by design.