In some embodiments, the series of {TAIL ~ indices} are created over a column that is typically searched using the LIKE predicate or some similar technique; {HEAD ~ these indices} indicate for each record whether certain sub strings may exist in that records value in the column 
In some embodiments , the series of { TAIL ~ indices } are created over a column that is typically searched using the LIKE predicate or some similar technique ; { HEAD ~ these indices } indicate for each record whether certain sub strings may exist in that records value in the column
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH