I have been working on the 2nd Edition of Data Modeling Made Simple, and the last chapter addresses several new challenges including this one on XML:
Here is a subset of a recipe XML document:
<ingredient amount=”4″ unit=”cup”>Flour</ingredient>
<ingredient amount=”10″ unit=”tablespoons”>Yeast</ingredient>
<ingredient amount=”2″ unit=” cup”>Water</ingredient>
<ingredient amount=”1″ unit=”teaspoon”>Salt</ingredient>
Would you consider an XML document to be a logical data model or a physical data model (or neither) and why?