On Sun, Sep 27, 2009 at 2:22 PM, David Fetter <david@xxxxxxxxxx> wrote: > On Sun, Sep 27, 2009 at 08:26:27PM +0200, InterRob wrote: >> Dear David, dear all, >> I very well understand what you are saying... > > Clearly you do not. What you are proposing has been tried many, many > times before, and universally fails. I've been refraining from jumping on this due to time constraints, but this statement is silly. We have a system that does almost exactly what the OP wants although the implementation is slightly different: we use an EAV like model with strong typing and build set / subset forests to maintain arbitrary hierarchies of relationships. Our reasons for doing this are similar to the OPs; it's for research (in our case medical research). We maintain over 200,000 pieces of end user generated metadata, describing what would be in a conventional relational model over 20,000 columns and some 1,000s of tables but the actual physical model is some 40 tables. Yes, the flip side is, such a system won't support more than 1,000,000s of transactions per day, but that's not why you build them. > > That your people are failing to get together and agree to a data model > is not a reason for you to prop up their failure with a technological > "fix" that you know from the outset can't be made to work. > Spoken like someone who has always had the luxury of working in areas with well defined problem domains... I can't tell you the number of people that told us exactly the same thing when we started on it. That was 8 years ago. Not only can such systems be built, they can be made to scale reasonably well. You do need to understand what you are doing and why: the costs can be high, but when it comes to research, the benefits can far outweigh the costs. -- Peter Hunsberger -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
