Re: Modeling As Data Or Metadata?

From: Karel van der Walt <karelvdwalt_at_webmail.co.za>
Date: Thu, 28 Mar 2002 09:11:24 +0200
Message-ID: <a7ufn0$nv8$1_at_newnews.mikom.csir.co.za>

 What i do is to differentaite between quantitative , qualitative and  descriptive observations : for descr attributes you use free text, for  qualitative you use either a domain or a lookup table (e.g. high, medium,  low) and for quant you use numeric value and a unit (This is a scenario that
 makes J celko whince...)

 Now to collect all your dynamic attributes together as columns you just  forfeited the declararive power of sql - you need to dynamically make up the
 sql to pivot rows out to columns. This you can do with a statement that  contains a selfjoin for every dynamic attribute. This statement has a  regular form and is easy manipulated in code (factory /builder class on  client OR a stored procedure if your sql support execute immediate of  dynamically constructed sql)

 In my mind the next best thing after stable attributes is a predictable  pattern of changes for new attributes.

 I would appreciate any feedback as much as you on this ;-) Received on Thu Mar 28 2002 - 08:11:24 CET