In particular, system 301 may provide several grouping operators that analyze and consolidate {HEAD ~ data} from {TAIL ~ multiple streams} 
from
In particular , system 301 may provide several grouping operators that analyze and consolidate { HEAD ~ data } from { TAIL ~ multiple streams }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL