Good article. However, I as a programmer have been asked to break rule #1, "Data is atomic. That means the intersection of a column and a row can only contain one single value," many times. At times I have been asked to put into one field the following values:

1. Parameter strings

2. xml

3. Delimited lists

4. Integers that are interpreted via bit-wise operators for multiple boolean values.

Are there any justifications for these practices?

Any comments?