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  • sql server行转列

    创建测试数据

    学生表 Student

    create table Student(S# varchar(10),Sname nvarchar(10),Sage datetime,Ssex nvarchar(10))
    insert into Student values('01' , N'赵雷' , '1990-01-01' , N'男')
    insert into Student values('02' , N'钱电' , '1990-12-21' , N'男')
    insert into Student values('03' , N'孙风' , '1990-05-20' , N'男')
    insert into Student values('04' , N'李云' , '1990-08-06' , N'男')
    insert into Student values('05' , N'周梅' , '1991-12-01' , N'女')
    insert into Student values('06' , N'吴兰' , '1992-03-01' , N'女')
    insert into Student values('07' , N'郑竹' , '1989-07-01' , N'女')
    insert into Student values('08' , N'王菊' , '1990-01-20' , N'女')

    科目表 Course
    create table Course(C# varchar(10),Cname nvarchar(10),T# varchar(10))
    insert into Course values('01' , N'语文' , '02')
    insert into Course values('02' , N'数学' , '01')
    insert into Course values('03' , N'英语' , '03')

    教师表 Teacher
    create table Teacher(T# varchar(10),Tname nvarchar(10))
    insert into Teacher values('01' , N'张三')
    insert into Teacher values('02' , N'李四')
    insert into Teacher values('03' , N'王五')

    成绩表 SC
    create table SC(S# varchar(10),C# varchar(10),score decimal(18,1))
    insert into SC values('01' , '01' , 80)
    insert into SC values('01' , '02' , 90)
    insert into SC values('01' , '03' , 99)
    insert into SC values('02' , '01' , 70)
    insert into SC values('02' , '02' , 60)
    insert into SC values('02' , '03' , 80)
    insert into SC values('03' , '01' , 80)
    insert into SC values('03' , '02' , 80)
    insert into SC values('03' , '03' , 80)
    insert into SC values('04' , '01' , 50)
    insert into SC values('04' , '02' , 30)
    insert into SC values('04' , '03' , 20)
    insert into SC values('05' , '01' , 76)
    insert into SC values('05' , '02' , 87)
    insert into SC values('06' , '01' , 31)
    insert into SC values('06' , '03' , 34)
    insert into SC values('07' , '02' , 89)
    insert into SC values('07' , '03' , 98)

    普通连表sql:

    select ST.Sname,Sage,Ssex,Score.score,CS.Cname from Student ST left join sc Score on ST.S#=Score.S# left join Course CS on Score.C#=CS.C#

    结果:

    行转列sql:

    select * from
    (
    select ST.Sname,Sage,Ssex,Score.score,CS.Cname from Student ST left join sc Score on ST.S#=Score.S# left join Course CS on Score.C#=CS.C# 
    
    )t
    pivot ( Max(score) for Cname in (语文,数学,英语)) as ourpivot

    结果:

    行转列还有一种方法:for xml path,多个表连接的话用这个比较难,有没有会的网友指点下

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  • 原文地址:https://www.cnblogs.com/codeDevotee/p/11121343.html
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