presto-tpcds/src/main/java/io/prestosql/plugin/tpcds/TpcdsRecordSet.java/TpcdsRecordSet/getSlice
class TpcdsRecordSet:        @Override
        public Slice getSlice(int field)
        {
            checkState(row != null, "No current row");
            Column column = columns.get(field);
            if (column.getType().getBase() == ColumnType.Base.DECIMAL) {
                return (Slice) Decimals.parse(row.get(column.getPosition())).getObject();
            }

            Slice characters = Slices.utf8Slice(row.get(columns.get(field).getPosition()));
            if (column.getType().getBase() == ColumnType.Base.CHAR) {
                characters = trimTrailingSpaces(characters);
            }
            return characters;
        }