Business Metadata: Capturing Enterprise Knowledge

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4.2.1.4 Units of Measure Differences

Another way that formulas can appear to be all apples but have oranges hiding

in their midst is when you have different units of measure. This is a very

insidious problem because all looks normal on the surface, and indeed it may

go undetected for a long period of time.

The classic example is the Mars orbiter problem back in 1999, which

we introduced in the beginning of this chapter. Here is a quote from CNN

concerning this data screw-up:

NASA lost a $125 million Mars orbiter because a Lockheed Martin engineering

team used English units of measurement while the agency’s team used the more

conventional metric ...