Need query for connecting flights

Question

Hi all.
My requirement is as follows
suppose my itnery is AAA-BBB-CCC.And there are few flights between AAA-BBB and BBB-CCC.I need all the valid connecting flights everyday.My table data is as follows
orig dest fltno arrivaldate depdate legno itid
AAA BBB 121 23-05-2011 15:40:00(arrical ar BBB) 1 x
AAA BBB 123 23-05-2011 16:40:00(arrical ar BBB) 1 x
BBB CCC 212 24-05-2011 04:05:00(arrical ar CCC) 23-05-2011 19:50:00(depat from BBB) 2 x
BBB CCC 213 24-05-2011 13:05:00 (arrical ar CCC) 24-05-2011 04:50:00(depat from BBB) 2 x
now i need to get for legno 1 all the flights in leg 2, whose depdate is grater than arrival date in leg 1.
Thanks.

Answer 1

Hi,
Whenever you have a problem, please post CREATE TABLE and INSERT statements for the sample data. Also post the results you want from that data, and an explanation of how you get those results from that data, with specific examples.
Always say which version of Oracle you're using.
If I understand the problem, then you can use somehting like this:
SELECT     l2.*
FROM     table_x       l1
JOIN     table_x       l2   ON   l2.legeno     = l1.legno + 1
                 AND  l2.orig     = l1.dest
                 AND  l2.depdate     > l1.arrivaldate
WHERE     l1.legno     = 1
;A self-join, like this, will work if you're looking for a specific leg. If you're interested in all legs (or all legs after a certain point), regardless of whether that's 1, 2, 3 or more, then use CONNECT BY instead of a self-join.