Hi, A very simple implementation of my idea:
http://h2database.com/p.html#e5e5d0fa3aabc42932e6065a37b1f6a8 The method hasSameNameSibling() that is called for each remove(). If it turns out to be a performance problem we could add a hidden property in the first SNS node itself (only required there). Does anybody see any other obvious problems? Regards, Thomas