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在mysql数据库中 rank的用法

【计算机英语】 2016-03-20本文已影响

  在mysql数据库中 rank的用法的用法你知道吗?下面小编就跟你们详细介绍下在mysql数据库中 rank的用法的用法,希望对你们有用。

  在mysql数据库中 rank的用法的用法如下:

  Write a SQL query to rank scores. If there is a tie between two scores, both should have the same ranking. Note that after a tie, the next ranking number should be the next consecutive integer value. In other words, there should be no "holes" between ranks.

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  +----+-------+

  | Id | Score |

  +----+-------+

  | 1 ?| 3.50 ?|

  | 2 ?| 3.65 ?|

  | 3 ?| 4.00 ?|

  | 4 ?| 3.85 ?|

  | 5 ?| 4.00 ?|

  | 6 ?| 3.65 ?|

  +----+-------+

  For example, given the above Scores table, your query should generate the following report (order by highest score):

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  +-------+------+

  | Score | Rank |

  +-------+------+

  | 4.00 ?| 1 ? ?|

  | 4.00 ?| 1 ? ?|

  | 3.85 ?| 2 ? ?|

  | 3.65 ?| 3 ? ?|

  | 3.65 ?| 3 ? ?|

  | 3.50 ?| 4 ? ?|

  +-------+------+

  题目解答:

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  # Write your MySQL query statement below

  SELECT Scores.Score, COUNT(Ranking.Score) AS RANK

  FROM Scores

  , (

  SELECT DISTINCT Score

  FROM Scores

  ) Ranking

  WHERE Scores.Score <= Ranking.Score

  GROUP BY Scores.Id, Scores.Score

  ORDER BY Scores.Score DESC;

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