Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7) Gecko/20040616
's','o','a','p' is ok as a constraint because it is fixed and well
I think the current_medication attribute value range constraints for
attributes form and and amount_unit , should be normalized into type
tables with id and description,
because it is easier to internationalize , and for applications to
conform to (eg reading type descriptions as values for combo/list boxes
in a gui or web app).