The invention relates to {HEAD ~ database management systems}, and in particular, to generating one or more indices over {TAIL ~ a table column} 
The invention relates to { HEAD ~ database management systems } , and in particular , to generating one or more indices over { TAIL ~ a table column }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL