Re: More on identifiers
Date: Fri, 5 Jun 2009 14:19:15 -0700 (PDT)
The usual model is that this is a collective/ aggregate/ bulk/ commodity entity (grains of sand, etc.) whose identity for DB purposes does not involve separate units. We talk in terms of lots with attributes like weight, volume, etc.
But the rules are weird -- lot A of #2 cooking oil can be added to lot B of #2 cooking oil to produce Lot C. Is it a new entity? If I split lot C into lots A and B, what is the data model? If I do a blend of oils in the batches, what is it? Etc.
This is a classic discrete (digitial) versus analog (continous) models of data problem. Received on Fri Jun 05 2009 - 23:19:15 CEST