A block layout generator produces {HEAD ~ interface objects} to be included within {TAIL ~ an interface} of the database, wherein each of the interface objects corresponds to one of the block descriptions and includes a plurality of layout fields 
to be included within
A block layout generator produces { HEAD ~ interface objects } to be included within { TAIL ~ an interface } of the database , wherein each of the interface objects corresponds to one of the block descriptions and includes a plurality of layout fields
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH