and { only { filter_eq { filter_less { all_rows ; elevation ( m ) ; 3000 } ; col ( m ) ; 0 } } ; eq { hop { filter_eq { filter_less { all_rows ; elevation ( m ) ; 3000 } ; col ( m ) ; 0 } ; peak } ; mount ruapehu } } = true
select the rows whose elevation  m  record is less than 3000 . among these rows , select the rows whose col  m  record is equal to 0 . there is only one such row in the table . the peak record of this unqiue row is mount ruapehu .