LISTAGGを見てください
http://www.oracle-base.com/articles/misc/StringAggregationTechniques.php
次のようなもの:
SELECT NAME, LISTAGG(CAR, ',') WITHIN GROUP (ORDER BY CAR) AS CARS
FROM (SELECT NAME,CAR
FROM TABLE1, TABLE2
where TABLE1.IdN=TABLE2.IdC)
GROUP BY NAME;