On Sun, 12 Feb 2012 16:16:26 +1100 Konrad Zielinski <[email protected]> wrote:
> Hi, > > I'm trying to work out the proper way to setup a master detail > relationship in a Picolisp database. > > I have a master record with child records where each child record is a > string and a number. Different master records do not at all care about > each others details. > And really The detail records will never be accessed outside the > context of the master record. They don't need any indexing, or > independent lookup. > > so is this the way you would do this? > > (class +Child +Entity) > (rel description (+Key +String)) > (rel rank (+Number)) > > (class +Master +Entity) > (rel children (+List +Link) ord (+Child)) > > Also As master records don;t relate to each other I'm a little > confused as to how I hand the rest of the database together. > Do I just start it and add objects to it Or do I need to build a top > level List of master objects and set this as the first object > in the database. > > regards > > Konrad > Hmm, isn't this type of relationship covered by the +Ord and +Pos classes in the example app included in picolisp's sources? # @app/er.l (class +Ord +Entity) (rel nr (+Need +Key +Number)) # Order Number [...] (rel pos (+List +Joint) ord (+Pos)) # Positions (class +Pos +Entity) (rel ord (+Dep +Joint) # Order (itm) pos (+Ord) ) [...] Orders (masters) are keyed by the order number and +Pos "Order Items" are linked to the order by a +Joint +List. Cheers, José -- UNSUBSCRIBE: mailto:[email protected]?subject=Unsubscribe
