Re: Organisational question: surely someone has implemented many Boolean values (tags) and a solution exist

On Thu, Jan 20, 2011 at 19:21, Richard Quadling <rquadling@gmail.com> wrote: >> That is terrific, at least the first half. The second half, with the >> Venn diagrams, is awkward! > > When you get heavily nested data, the adjacent set model (where you > have a parentid for every uniqueid), you very quickly get into > complicated logic trying to traverse n-levels. The nested set model is > specifically built to handle this issue. I'd recommend getting to > grips with it. It will make finding items belonging to a group (or a > super group) a LOT easier. > > Especially if you have multiple tag hierarchies. > Is that strategy widely deployed, then? It seems so unruly having to change on average half the database records for every new leaf. -- Dotan Cohen http://gibberish.co.il http://what-is-what.com