presto-main/src/main/java/io/prestosql/operator/index/UnloadedIndexKeyRecordSet.java/UnloadedIndexKeyRecordCursor/getBoolean
class UnloadedIndexKeyRecordCursor:        @Override
        public boolean getBoolean(int field)
        {
            return types.get(field).getBoolean(page.getBlock(field), position);
        }