Re: Demo: Modelling Cost of Travel Paths Between Towns
Date: 3 Dec 2004 08:44:35 -0800
Message-ID: <4b45d3ad.0412030844.5d0ee8f6_at_posting.google.com>
> What does the DDL look like? e.g. "aspirin is a thing",
> "tylenol is a thing", "Nyquil is a thing" etc. some are "cold medecines",
> which are a sub-class of medicines, but some could be
> used as simply a "headache remedy."
> Thus they belong to two hierarchies.
// Create classes to categorize things
CREATE *medicine.cls = thing; CREATE *headache remedy.cls = thing; CREATE *cold medicine.cls = thing;
// Assuming asprin is a medicine and headache remedy
CREATE *asprin.cls = medicine;
CREATE asprin.cls = headache remedy;
// Assuming tylenol is a medicine and cold medicine
CREATE *tylenol.cls = medicine;
CREATE tylenol.cls = cold medicine;
// Assuming nyquil is a medicine, headache remedy and cold medicine
CREATE *nyquil.cls = medicine;
CREATE nyquil.cls = headache remedy;
CREATE nyquil.cls = cold medicine;
// Assuming garlic is a headache remedy and cold medicine
// but not a medicine
CREATE *garlic.cls = headache remedy;
CREATE garlic.cls = cold medicine;
// Assuming ginger is a cold medicine only CREATE *ginger.cls = cold medicine;
Please show RM's equivalent without NULLs and redundant data. Received on Fri Dec 03 2004 - 17:44:35 CET