// for Tables, we can get this directly
s = ((Table)ts).getSchema();
} else {
// if non-table tuple set is empty, we punt
if ( ts.getTupleCount() == 0 )
return new NullComparator();
// otherwise, use the schema of the first tuple in the set
s = ((Tuple)ts.tuples().next()).getSchema();
}
// create the comparator
CompositeComparator cc = new CompositeComparator(m_fields.length);