name subject
A 语文 80
A 数学 80
A 外语 80
B 数学 80
B 外语 80
C 语文 78姓名 语文 数学 外语 avg
A 80 80 80 80
B 0 80 80 53
C 78 0 0 16请用sql语句将上面的表转换成下表....
A 语文 80
A 数学 80
A 外语 80
B 数学 80
B 外语 80
C 语文 78姓名 语文 数学 外语 avg
A 80 80 80 80
B 0 80 80 53
C 78 0 0 16请用sql语句将上面的表转换成下表....
insert into T select 'A','语文','80'
insert into T select 'A','数学','80'
insert into T select 'A','外语','80'
insert into T select 'B','数学','80'
insert into T select 'B','外语','80'
insert into T select 'C','语文','78'
select
name,
sum(case when subject ='语文' then else 0 end ) as 语文,
sum(case when subject ='数学' then else 0 end ) as 数学,
sum(case when subject ='外语' then else 0 end ) as 外语,
sum()/3 as d
from T
group by Namedrop table T
name as 姓名,
sum(case when subject ='语文' then else 0 end ) as 语文,
sum(case when subject ='数学' then else 0 end ) as 数学,
sum(case when subject ='外语' then else 0 end ) as 外语,
sum()/3 as avg
from T
group by Name
max(case subject when '外语' then else 0 end )as [外语] ,
max(case subject when '语文' then else 0 end )as [语文] ,avg() as [平均分]
from @t group by name
*/
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想变成
姓名 语文 数学 物理
张三 73 83 93
李四 74 84 94create table #t
(
Name varchar(10) ,
Subject varchar(10) ,
Result int
)insert into #t(Name , Subject , Result) values('张三','语文','73')
insert into #t(Name , Subject , Result) values('张三','数学','83')
insert into #t(Name , Subject , Result) values('张三','物理','93')
insert into #t(Name , Subject , Result) values('李四','语文','74')
insert into #t(Name , Subject , Result) values('李四','数学','83')
insert into #t(Name , Subject , Result) values('李四','物理','93')declare @sql varchar(8000)
set @sql = 'select Name as ' + '姓名'
select @sql = @sql + ' , sum(case Subject when ''' + Subject + ''' then Result end) [' + Subject + ']'
from (select distinct Subject from #t) as a
set @sql = @sql + ' from #t group by name'
exec(@sql) drop table #t--结果
姓名 数学 物理 语文
---------- ----------- ----------- -----------
李四 83 93 74
张三 83 93 73
----------------------------------------------------
如果上述两表互相换一下:即姓名 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 94create table #t
(
姓名 varchar(10) ,
语文 int ,
数学 int ,
物理 int
)insert into #t(姓名 , 语文 , 数学 , 物理) values('张三',73,83,93)
insert into #t(姓名 , 语文 , 数学 , 物理) values('李四',74,84,94)select 姓名 as Name,'语文' as Subject,语文 as Result from #t union
select 姓名 as Name,'数学' as Subject,数学 as Result from #t union
select 姓名 as Name,'物理' as Subject,物理 as Result from #t
order by 姓名 desc drop table #t
--结果
Name Subject Result
---------- ------- -----------
张三 数学 83
张三 物理 93
张三 语文 73
李四 数学 84
李四 物理 94
李四 语文 74(所影响的行数为 6 行)
insert into T select 'A','語文','80'
insert into T select 'A','數學','80'
insert into T select 'A','外語','80'
insert into T select 'B','數學','80'
insert into T select 'B','外語','80'
insert into T select 'C','語文','78'--靜態sqlselect name ,
sum(case when subject='語文' then else 0 end)as '語文',
sum(case when subject='數學' then else 0 end)as '數學',
sum(case when subject='外語' then else 0 end)as '外語'
from t
group by name--動態sqldeclare @str varchar(1000)
set @str='select name '
select @str=@str+',sum(case when subject='''+subject+''' then else 0 end)as '''+subject+''''
from t
group by subject
select @str=@str+' from t group by name'
exec(@str)
name 外語 語文 數學
---------------------------------------------------------------------------------------------------- ----------- ----------- -----------
A 80 80 80
B 80 0 80
C 0 78 0
insert into t
select 'A','語文',80 union all
select 'A','數學',80 union all
select 'A','外語',80 union all
select 'B','數學',80 union all
select 'B','外語',80 union all
select 'C','語文',78declare @sql varchar(8000),@count int
select @count=count(distinct subject) from T
set @sql='select name'
select @sql=@sql+',sum(case when subject='''+subject+''' then else 0 end) as '+subject
from T
group by subjectselect @sql=@sql+',sum(isnull(,0))/'+rtrim(@count)+' as [avg] from t group by name'
exec(@sql)
/*
name 外語 語文 數學 avg
---- ----------- ----------- ----------- -----------
A 80 80 80 80
B 80 0 80 53
C 0 78 0 26
*/
drop table t
insert into tb values('A', '数学', 80)
insert into tb values('A', '外语', 80 )
insert into tb values('B', '数学', 80)
insert into tb values('B', '外语', 80)
insert into tb values('C', '语文', 78)select name ,
max(case subject when '语文' then else 0 end) '语文',
max(case subject when '数学' then else 0 end) '数学',
max(case subject when '外语' then else 0 end) '外语',
sum()/(select max(cnt) cnt from (select name , count(*) cnt from tb group by name) t) [avg]
from tb
group by namedrop table tb/*
name 语文 数学 外语 avg
---------- ----------- ----------- ----------- -----------
A 80 80 80 80
B 0 80 80 53
C 78 0 0 26(所影响的行数为 3 行)
*/
insert into tb values('A', '数学', 80)
insert into tb values('A', '外语', 80 )
insert into tb values('B', '数学', 80)
insert into tb values('B', '外语', 80)
insert into tb values('C', '语文', 78)select name ,
max(case subject when '语文' then else 0 end) '语文',
max(case subject when '数学' then else 0 end) '数学',
max(case subject when '外语' then else 0 end) '外语',
sum()/(select max(cnt) cnt from (select name , count(*) cnt from tb group by name) t) [avg]
from tb
group by namedeclare @sql varchar(8000)
set @sql = 'select Name as ' + '姓名'
select @sql = @sql + ' , sum(case Subject when ''' + Subject + ''' then else 0 end) [' + Subject + ']'
from (select distinct Subject from tb) as a
set @sql = @sql + ' ,sum()/(select max(cnt) cnt from (select name , count(*) cnt from tb group by name) t) [avg] from tb group by name'
exec(@sql) drop table tb/*
name 语文 数学 外语 avg
---------- ----------- ----------- ----------- -----------
A 80 80 80 80
B 0 80 80 53
C 78 0 0 26(所影响的行数为 3 行)姓名 数学 外语 语文 avg
---------- ----------- ----------- ----------- -----------
A 80 80 80 80
B 80 80 0 53
C 0 0 78 26
*/
insert into T select 'A','語文','80'
insert into T select 'A','數學','80'
insert into T select 'A','外語','80'
insert into T select 'B','數學','80'
insert into T select 'B','外語','80'
insert into T select 'C','語文','78'--靜態sqlselect name ,
sum(case when subject='語文' then else 0 end)as '語文',
sum(case when subject='數學' then else 0 end)as '數學',
sum(case when subject='外語' then else 0 end)as '外語',
sum()/(select count(distinct subject)from t )
from t
group by name--動態sqldeclare @str varchar(1000)
set @str='select name '
select @str=@str+',sum(case when subject='''+subject+''' then else 0 end)as '''+subject+''''
from t
group by subject
select @str=@str+',sum()/(select count(distinct subject ) from t) from t group by name'
exec(@str)name 外語 語文 數學 avge
---------------------------------------------------------------------------------------------------- ----------- ----------- ----------- -----------
A 80 80 80 80
B 80 0 80 53
C 0 78 0 26