SQLZOO网页中SQL的答案

SELECT name,
               CASE WHEN continent IN (‘Asia‘,‘Europe‘) THEN ‘Eurasia‘
               WHEN continent IN (‘North America‘,‘South America‘,‘Caribbean‘) THEN ‘America‘
                ELSE continent END
FROM world
WHERE name LIKE ‘A%‘ OR name LIKE ‘B%‘

答案：

SELECT name,continent,
CASE WHEN continent IN (‘Eurasia‘, ‘Turkey‘)
     THEN ‘Europe/Asia‘

     WHEN continent = ‘Oceania‘ 
     THEN ‘Australasia‘

     WHEN continent = ‘Caribbean‘
          THEN
          CASE 
          WHEN name LIKE ‘B%‘ 
          THEN ‘North America‘
          ELSE ‘South America‘
          END
     ELSE continent 
     END
FROM world
ORDER BY name ASC;