 I was trying to be concise for a change, the price of which
     is that I had to try and paint this image of changing bases
     in very broad brush stokes indeed.  See my amendments above.
     You may well speculate on how I decided what amends to make.

JA:  It may serve a little to think of a Deductive Data Base or a Knowledge
Base,
     but really all I have in mind here is any sort of significant
restructuring.

DW:  I create, modify, or remove
     a field/column/data-element
     from a file/table