Det finns en elegant (och effektiv) lösning som använder match_recognize
klausul (som kräver Oracle 12.1 eller högre).
select po, startdate, enddate
from orders
match_recognize (
partition by po
order by startdate
measures first(startdate) as startdate, max(enddate) as enddate
pattern ( c* n )
define c as max(enddate) + 1 >= next(startdate)
);