eq { diff { hop { filter_eq { all_rows ; school ; perry central } ; size } ; hop { filter_eq { all_rows ; school ; springs valley } ; size } } ; 15 } = true
select the rows whose school record fuzzily matches to perry central . take the size record of this row . select the rows whose school record fuzzily matches to springs valley . take the size record of this row . the first record is 15 larger than the second record .