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Hogwash: Applying the First Normal Form
The article is replete with misinformation. Let's take it point-by-point:

1. Multivalued fields must be removed to another table.

This is a silly statement. In the strictest sense, a column is only capable of holding one value from the domain over which it is defined.

Using the term "values" more loosely, there is no restriction on how many a field may contain. Given "X" is a value, let the debate begin about how many values are in "XX" and "X,X". In any case, none violate 1NF. The strongest proof is that 1NF is a characteristic of the table, irrespective of the data it contains.

2. Each field must be atomic, or as small as possible.

I guess that would be a bit, right? What more can I say?

3. Each field must have a key. [So, the values in at least one field or column in a table must be unique.]

The actual requirement is that the table may not permit duplicate rows. While a primary key is the usual way to achieve that, there is no limitation on the number of columns it may contain.

4. Repeating values must be removed to another table.

Absurd. A value may repeat in different rows of the same column or different columns of the same row. Reading the author's explanation, I have no idea what this means.
Posted by millerdq@...
Updated - 9th Oct 2008