sql纵向表转成横向表

àì夳堔傛蜴生んèń 2022-04-10 08:40 271阅读 0赞

declare @tab table(Class varchar(20),Student varchar(20),Course varchar(50),Grades decimal(7,2));  
insert into @tab(Class,Student,Course,Grades) values('A班','张三','语文',60);  
insert into @tab(Class,Student,Course,Grades) values('A班','张三','数学',70);  
insert into @tab(Class,Student,Course,Grades) values('A班','张三','英语',80);  
insert into @tab(Class,Student,Course,Grades) values('A班','李四','语文',30);  
insert into @tab(Class,Student,Course,Grades) values('A班','李四','数学',40);  
insert into @tab(Class,Student,Course,Grades) values('A班','李四','英语',50);  
insert into @tab(Class,Student,Course,Grades) values('B班','王五','语文',65);  
insert into @tab(Class,Student,Course,Grades) values('B班','王五','数学',75);  
insert into @tab(Class,Student,Course,Grades) values('B班','王五','英语',85);  
insert into @tab(Class,Student,Course,Grades) values('B班','赵六','语文',35);  
insert into @tab(Class,Student,Course,Grades) values('B班','赵六','数学',45);  
insert into @tab(Class,Student,Course,Grades) values('B班','赵六','英语',55);  
  
select \* from @tab  
  
select  
(case when Grouping(Class)=1 then '总平均' when Grouping(Student)=1 then '' else Class end ) as Class  
,(case when Grouping(Class)=1 then '' when Grouping(Student)=1 then '平均' else Student end) as Student  
,cast(avg(语文) as decimal(7,2)) as 语文  
,cast(avg(数学) as decimal(7,2)) as 数学  
,cast(avg(英语) as decimal(7,2)) as 英语  
,cast(avg(总分) as decimal(7,2)) as 总分  
from (  
select Class,Student  
,(select isnull(sum(Grades),0) from @tab where class="t".Class and Student=t.Student and Course='语文') as '语文'  
,(select isnull(sum(Grades),0) from @tab where class="t".Class and Student=t.Student and Course='数学') as '数学'  
,(select isnull(sum(Grades),0) from @tab where class="t".Class and Student=t.Student and Course='英语') as '英语'  
,(select isnull(sum(Grades),0) from @tab where class="t".Class and Student=t.Student) as '总分'  
from @tab as t  
group by Class,Student  
) as tempTab  
group by Class,Student,语文,数学,英语,总分 with rollup  
having Grouping(语文)=1  
and Grouping(数学)=1  
and Grouping(英语)=1

--------------------

SQL语句之普通行列转换

假设有张学生成绩表(Result)如下  
Name Subject Result  
张三 语文　　73  
张三 数学　　83  
张三  
物理　　93  
李四 语文　　74  
李四 数学　　84  
李四 物理　　94

建表:

create TABLE TABLE1 (Name varchar(50),Subject varchar(50),Result int)  
  
INSERT INTO TABLE1 VALUES('张三','语文','73')  
INSERT INTO TABLE1  
VALUES('张三','数学','83')  
INSERT INTO TABLE1 VALUES('张三','物理','93')  
INSERT  
INTO TABLE1 VALUES('李四','语文','74')  
INSERT INTO TABLE1  
VALUES('李四','数学','84')  
INSERT INTO TABLE1 VALUES('李四','物理','94')

想变成  
姓名 语文 数学 物理  
张三 73　　83　　93  
李四 74　　84　　94

declare @sql varchar(4000)  
set @sql = 'select Name as ' + '姓名'  
select  
@sql = @sql + ' , sum(case Subject when '''+Subject+''' then Result end)  
\['+Subject+'\]'  
from (select distinct Subject from TABLE1) as a  
set @sql =  
@sql + ' from TABLE1 group by name'  
exec(@sql)

如果上述两表互相换一下：即  
表名(cj)  
姓名 语文 数学 物理  
张三 73　　83　　93  
李四 74　　84　　94

想变成

Name Subject Result  
张三 语文　　73  
张三 数学　　83  
张三 物理　　93  
李四 语文　　74  
李四  
数学　　84  
李四 物理　　94

select 姓名 as Name,'语文' as Subject,语文 as Result from CJ union  
select 姓名 as  
Name,'数学' as Subject,数学 as Result from CJ union  
select 姓名 as Name,'物理' as  
Subject,物理 as Result from CJ  
order by 姓名 desc