-- Query the two cities in STATION with the shortest and longest CITY names,

-- as well as their respective lengths (i.e.: number of characters in the name).

-- If there is more than one smallest or largest city, choose the one that comes first when ordered alphabetically.

-- CASE1 OK

SELECT CITY, LENGTH(CITY)

FROM (SELECT CITY, LENGTH(CITY) AS LENG

FROM STATION

ORDER BY LENG, CITY)

WHERE ROWNUM <= 1

UNION

SELECT CITY, LENGTH(CITY)

FROM (SELECT CITY, LENGTH(CITY) AS LENG

FROM STATION

ORDER BY LENG DESC, CITY)

WHERE ROWNUM <= 1;

-- CASE2 OK

SELECT CITY, LENGTH(CITY)

FROM (SELECT CITY,

ROW_NUMBER() OVER(ORDER BY LENGTH(CITY), CITY) AS RN,

COUNT(*) OVER() AS CNT

FROM STATION)

WHERE RN IN (1, CNT);