/* Q20. Group customers by their */ /* income and output the cardinality of each group. */ /* EMPTY is not handled. converted into count() = 0 */ COUNT (document("RainbowCore/Xmark/auction.xml")/people/person/profile[@income .>=. 100000]) , COUNT (document("RainbowCore/Xmark/auction.xml")/people/person/profile[@income .<. 100000 and @income .>=. 30000]) , COUNT (document("RainbowCore/Xmark/auction.xml")/people/person/profile[@income .<. 30000]) , COUNT (FOR $p in document("RainbowCore/Xmark/auction.xml")/people/person WHERE COUNT($p/@income) = 0 RETURN $p)