Question

我有一个包含多个运动队和运动项目的Oracle数据库表。现在，我需要为每个运动项分配最低的3个团队（如果少于3个，则更少）（基于他们的ID）。

（在我的例子中，足球：巴塞罗那，皇家马德里，PSG /曲棍球：纽约岛民，纳什维尔掠食者，波士顿熊/篮球：洛杉矶湖人队，波士顿凯尔特人，克利夫兰骑士/棒球：纽约洋基）

我的表格/条目：

Create Table Teams(
teamid NUMBER,
teamname VARCHAR(20),
Sport VARCHAR(20)
);



INSERT INTO Teams (teamid, teamname, Sport) values (1, 'Barcelona', 'Soccer');
INSERT INTO Teams (teamid, teamname, Sport) values (2, 'Real Madrid', 'Soccer');
INSERT INTO Teams (teamid, teamname, Sport) values (3, 'PSG', 'Soccer');
INSERT INTO Teams (teamid, teamname, Sport) values (4, 'Liverpool', 'Soccer');
INSERT INTO Teams (teamid, teamname, Sport) values (5, 'Bayern Munich', 'Soccer');

INSERT INTO Teams (teamid, teamname, Sport) values (6, 'NY Islanders', 'Hockey');
INSERT INTO Teams (teamid, teamname, Sport) values (7, 'Nashville Predators', 'Hockey');
INSERT INTO Teams (teamid, teamname, Sport) values (8, 'Boston Bruins', 'Hockey');
INSERT INTO Teams (teamid, teamname, Sport) values (9, 'Vancouver Canucks', 'Hockey');
INSERT INTO Teams (teamid, teamname, Sport) values (10, 'NY Rangers', 'Hockey');

INSERT INTO Teams (teamid, teamname, Sport) values (11, 'LA Lakers', 'Basketball');
INSERT INTO Teams (teamid, teamname, Sport) values (12, 'Boston Celtics', 'Basketball');
INSERT INTO Teams (teamid, teamname, Sport) values (13, 'Cleveland Cavaliers', 'Basketball');
INSERT INTO Teams (teamid, teamname, Sport) values (14, 'Huston Rockets', 'Basketball');
INSERT INTO Teams (teamid, teamname, Sport) values (15, 'Chicago Bulls', 'Basketball');

INSERT INTO Teams (teamid, teamname, Sport) values (16, 'NY Yankees', 'Baseball');

我已经尝试过：Get top results for each group (in Oracle)，但我仍然拥有所有团队。

基于示例的“我的选择语句”：

SELECT t.teamname, t.sport 
FROM teams t
  LEFT OUTER JOIN teams t2 
    ON (t.teamname = t2.teamname AND t.teamid <= t2.teamid) 
GROUP BY t.teamid, t.teamname, t.sport
HAVING COUNT(*) <= 3 
ORDER BY t.sport asc;

Answer 1

一个选项使用ROW_NUMBER：

SELECT teamid, teamname, Sport
FROM
(
    SELECT t.*, ROW_NUMBER() OVER (PARTITION BY Sport ORDER BY teamid) rn
    FROM Teams t
) s
WHERE rn <= 3
ORDER BY Sport, teamid;

Oracle SQL：获得每个“类别”的前3个结果

1 个答案: