less { hop { filter_eq { all_rows ; dam constructed ; tooma dam } ; year completed } ; hop { filter_eq { all_rows ; dam constructed ; talbingo dam } ; year completed } } = true
select the rows whose dam constructed record fuzzily matches to tooma dam . take the year completed record of this row . select the rows whose dam constructed record fuzzily matches to talbingo dam . take the year completed record of this row . the first record is less than the second record .