SQLZOO 정답: 9 - Windows 기능

Show the lastName, party and votes for the constituency ‘S14000024’ in 2017.

SELECT lastName, party, votes
  FROM ge
 WHERE constituency = 'S14000024' AND yr = 2017
ORDER BY votes DESC

Show the party and RANK for constituency S14000024 in 2017. List the output by party.

SELECT party, votes,
       RANK() OVER (ORDER BY votes DESC) as posn
  FROM ge
 WHERE constituency = 'S14000024' AND yr = 2017
ORDER BY party

Use PARTITION to show the ranking of each party in S14000021 in each year. Include yr, party, votes and ranking (the party with the most votes is 1).

SELECT yr,party, votes,
      RANK() OVER (PARTITION BY yr ORDER BY votes DESC) as posn
  FROM ge
 WHERE constituency = 'S14000021'
ORDER BY party,yr

Use PARTITION BY constituency to show the ranking of each party in Edinburgh in 2017. Order your results so the winners are shown first, then ordered by constituency.

SELECT constituency,party, votes,
RANK() OVER (PARTITION BY constituency ORDER BY votes DESC) as posn
  FROM ge
 WHERE constituency BETWEEN 'S14000021' AND 'S14000026'
   AND yr  = 2017
ORDER BY posn,constituency

Show the parties that won for each Edinburgh constituency in 2017.

SELECT constituency,party FROM
(SELECT constituency,party, votes,
RANK() OVER (PARTITION BY constituency ORDER BY votes DESC) as posn
  FROM ge
 WHERE constituency BETWEEN 'S14000021' AND 'S14000026'
   AND yr  = 2017) RK
WHERE RK.posn=1

Show how many seats for each party in Scotland in 2017.

SELECT party,COUNT(*) FROM (
SELECT constituency,party, votes,
RANK() OVER (PARTITION BY constituency ORDER BY votes DESC) as posn
  FROM ge
 WHERE constituency LIKE 'S%'
   AND yr  = 2017) rk
WHERE rk.posn=1
GROUP BY rk.party

최근에 sql를 쓰고 있기 때문에 인터넷에서 답을 찾지 못하고 이 글을 썼습니다. 그 중에서 sql가 가장 좋은 것은 아닐 수도 있지만 결과는 문제없습니다.이것은 CSDN을 사용한 이래 첫 번째 CSDN 문장입니다. 여러분의 지적을 환영합니다.만약 여러분께 더 좋은 ql가 있다면, 아낌없이 메시지를 남겨 주십시오.