Chord symbol interpretation

After searching the Operations Manual and looking at the following 3 posts I could not figure out how to interpret what the Cubase Chord Display was showing.


http://www.steinberg.net/forums/viewtopic.php?f=196&t=53437&p=325827&hilit=+chord+symbols+#p325827

http://www.steinberg.net/forums/viewtopic.php?f=181&t=31928

http://www.steinberg.net/forums/viewtopic.php?f=198&t=33346&p=215287&hilit=+chord+symbols+#p215287

These are some of the chords in an old song of mine that Cubase displays as:

Db7/9, Bb9/9, Bb7/b9, Eb#9, C7/b9.

I understand the notes that the last three chords should be comprised of, but I have no idea, based on the symbols used in those three chords
how to interpret the first two chords Db7/9 or Bb9/9.

Anyone have any ideas?