On 19 September 2011 12:01, Koen Van Impe <koen.vani...@belnet.be> wrote:
> Hello, > > I'm trying to write a query that groups records by hour. > This works fine but when there are no records for a specific hour the > query does not return a result (this seems 'logic') and I'd like it to > return '0'. I suspect I should play around with 'interval' or something > but I can't get it to work. > If you're working with an interval of time that's known when issuing the query, you can add the missing hours by joining your results with generate_series(). If not, you'll probably have to create a table with enough dates and hours to join against, for which generate_series() is once again quite convenient. I'd like to see a resultset similar to this It works like this: select hours.h from generate_series(0, 23) AS hours(h); Alban. -- If you can't see the forest for the trees, Cut the trees and you'll see there is no forest.
