Re: Other tree representations in SQL

: For postorder:

:

Of course, if [seq] always starts with 1, then we could use:

SELECT :my_root, T1.*
  FROM Tree AS T1, Tree AS T2

 WHERE T2.node = :my_root
   AND T2.seq > T1.seq
   AND T1.level > T2.level
   AND T1.seq
       >= COALESCE((SELECT MAX(T3.seq)
                      FROM Tree AS T3
                     WHERE T3.level = T2.level
                       AND T3.seq < T2.seq), 1);

regards,
Damjan S. Vujnovic

University of Belgrade
School of Electrical Engineering
Department of Computer Engineering & Informatics Belgrade, Yugoslavia

http://galeb.etf.bg.ac.yu/~damjan/ Received on Thu Dec 05 2002 - 01:02:34 CET