sql 查詢每科的前三名

廢話不多說，直接上腳本 

CREATE TABLE [dbo].[Students](
    [ID] [int] IDENTITY(1,1) NOT NULL,
    [name] [nchar](20) NULL,
    [kemu] [nchar](20) NULL,
    [score] [int] NOT NULL,
 CONSTRAINT [PK_Students] PRIMARY KEY CLUSTERED 
(
    [ID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

insert into Students values('張三','語文',66)
insert into Students values('李四','語文',67)
insert into Students values('王五','語文',68)
insert into Students values('趙六','語文',69)
insert into Students values('天氣','語文',70)
insert into Students values('王八','語文',72)
insert into Students values('幺九','語文',75)
insert into Students values('大十','語文',80)



insert into Students values('張三','數學',85)
insert into Students values('李四','數學',80)
insert into Students values('王五','數學',75)
insert into Students values('趙六','數學',69)
insert into Students values('天氣','數學',68)
insert into Students values('王八','數學',67)
insert into Students values('幺九','數學',66)
insert into Students values('大十','數學',65)


insert into Students values('張三','英語',60)
insert into Students values('李四','英語',72)
insert into Students values('王五','英語',76)
insert into Students values('趙六','英語',77)
insert into Students values('天氣','英語',85)
insert into Students values('王八','英語',78)
insert into Students values('幺九','英語',75)
insert into Students values('大十','英語',71)

查詢語句：內層中  WHERE B.kemu = A.kemu  其實相當於 拿外層的 name  分組 group  by 

SELECT * 
FROM Students A
WHERE name IN (SELECT TOP 3 name
                       FROM Students B
                      WHERE B.kemu = A.kemu
                      ORDER BY B.score DESC)
ORDER BY A.kemu, A.score DESC

運行結果：