Re: MV and SQL

From: JOG <jog_at_cs.nott.ac.uk>
Date: 18 Jan 2006 06:34:27 -0800
Message-ID: <1137594867.405413.269740_at_o13g2000cwo.googlegroups.com>


Ok, I have a question, with a bit of a build up: RM is based on the satisfaction of a given predicate. First Order Logic holds however that if we have missing data then we simply have no satisfied predicate, and it should not be encoded. There is a clear strain on RM here (observe the huge debates on nulls) to attempt to provide a satisfactory resolution for this situation, yet is a situation that is extremely prevalent for three reasons:

  1. Incomplete Data at entry time.
  2. Incorrect Design.
  3. Static Design which no longer matches how the real world has shifted.

In my eyes the fact that these 3 things happen so frequently indicates that a system based on the satisfaction of a fixed predicate has poor application to the real world and that the RM's solid mathematical basis might be yet improved upon through integration of these issues. Data is almost always incomplete, a designer cannot be omniscient and will always make errors, but most importantly situations change. Continually. It is preferable that we have a database model that accomodates these factors: they are not orthogonal to data modelling processes in the real world.

Hence my question is does Pick go anywhere to accomodating these issues? If so, and given that it is clearly not the be all and end all of data storage, what are the crucial mechanisms that allows it to do so that might be of use in future systems? Received on Wed Jan 18 2006 - 15:34:27 CET

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