Andreas <maps.on@gmx.net> wrote: > Hi, > is there a clever way to check overlapping time intervals ? > An option named n should be taken from date y to y. > The same name is ok for another interval. > > e.g. table : mytab ( d1 date, d2 date, n text, v text ) > > There should be a constraint to provide no row can have a d1 or d2 > within the interval of another row in case they have the same n. > > And no row can have an interval that encloses an existing interval. You can use the PERIOD data type: http://temporal.projects.postgresql.org/reference.html and the new (since 9.0) exclusion constraint: http://www.depesz.com/index.php/2010/01/03/waiting-for-8-5-exclusion-constraints/ http://www.google.de/search?hl=de&q=postgresql+exclusion+constraint&aq=0L&aqi=g-L1&aql=&oq=postgresql+exclusion+ http://thoughts.j-davis.com/2010/03/09/temporal-postgresql-roadmap/ Andreas -- Really, I'm not out to destroy Microsoft. That will just be a completely unintentional side effect. (Linus Torvalds) "If I was god, I would recompile penguin with --enable-fly." (unknown) Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889°
pgsql-sql by date:
Соглашаюсь с условиями обработки персональных данных