例一:列轉行
drop table test
create table test (name char(10),km char(10),cj int)
go
insert test values('張三','語文',80)
insert test values('張三','數學',86)
insert test values('張三','英語',75)
insert test values('李四','語文',78)
insert test values('李四','數學',85)
insert test values('李四','英語',78)
select * from test
想變成
姓名 語文 數學 英語
張三 80 86 75
李四 78 85 78
動態的:
declare @sql varchar(8000)
set @sql = 'select name'
select @sql = @sql + ',sum(case km when '''+km+''' then cj end) ['+km+']'
from (select distinct km from test) as a
select @sql = @sql+' from test group by name'
print @sql
exec(@sql)
靜態的:
select name,
sum(case km when '數學 ' then cj end) [數學 ],
sum(case km when '英語 ' then cj end) [英語 ],
sum(case km when '語文 ' then cj end) [語文 ]
from test group by name
例二:列轉行
drop table t
create table t (cardno int,sex varchar(2),age int)
insert into t values (1,'男',12)
insert into t values (2,'男',10)
insert into t values (3,'女',14)
insert into t values (4,'女',18)
insert into t values (5,'男',20)
select * from t
動態的:
declare @sql varchar(8000)
set @sql='select a.id '
select @sql=@sql + ',sum(case a.sex when '''+ a.sex +''' then a.age end) ['+ a.sex+']'
from (select 1 as id,sex, avg(age) age from t group by sex) as a
select @sql = @sql + ' from (select 1 as id,sex,avg(age)age from t group by sex) as a group by a.id'
print @sql
exec (@sql)
靜態的:
select
sum(case a.sex when '男' then a.age end) [男],
sum(case a.sex when '女' then a.age end) [女]
from (select 1 as id,sex,avg(age)age from t group by sex) as a
group by a.id
例三:行轉列
drop table t1
create table t1 (a int,b int,c int,d int,e int,f int,g int,h int)
insert t1 values(15, 9, 1, 0, 1, 2, 2, 0)
動態的:
select * from t1
declare @a varchar(8000)
set @a=''
select @a=@a+rtrim(name)+' from t1 union all select ' from syscolumns where id=object_id('t1')
set @a=left(@a,len(@a)-len(' from t1 union all select '))
print @a
exec('select '+@a+' from t1')
靜態的:
select a from t1
union all
select b from t1
union all
select c from t1
union all select d from t1
union all
select e from t1
union all
select f from t1
union all
select g from t1
union all
select h from t1
例四:
有表A,
id pid
1 1
1 2
1 3
2 1
2 2
3 1
如何化成表B:
id pid
1 1,2,3
2 1,2
3 1
或者是從表B變成A(不要用遊標)
以前有相似的列子,現在找不到了,幫幫忙!
drop table t2
create table t2(id int,pid int)
insert into t2 values(1,1)
insert into t2 values(1,2)
insert into t2 values(1,3)
insert into t2 values(2,1)
insert into t2 values(2,2)
insert into t2 values(3,1)
select * from t2
--1.創建一個合併的函數
drop function fmerg
go
create function fmerg(@id int)
returns varchar(8000)
as
begin
declare @str varchar(8000)
set @str=''
select @str=@str+','+cast(pid as varchar) from t2 where id=@id
set @str=right(@str,len(@str)-1)
return(@str)
End
go
--2調用自定義函數得到結果
select distinct id,dbo.fmerg(id) from t2
例五:
drop table #t
create table #t(splb nvarchar(20),spm nvarchar(20),sl int,chr varchar(5))
insert #t select '水果','蘋果',20,'10/1'
union all select '水果','桔子',10,'10/1'
union all select '水果','桔子',30,'10/2'
union all select '糧食','大米',12,'10/1'
union all select '糧食','麥子',25,'10/4'
select * from #t
動態的:
declare @sql nvarchar(4000)
select @sql=N'select splb,spm'
select @sql=@sql+',sum(case when chr='''+chr+''' then sl else 0 end) as ['+chr+']'
from #t group by chr
select @sql=@sql+' from #t group by splb,spm order by splb desc'
print @sql
exec (@sql)
靜態的:
select splb,spm,
sum(case when chr='10/1' then sl else 0 end) as [10/1],
sum(case when chr='10/2' then sl else 0 end) as [10/2],
sum(case when chr='10/4' then sl else 0 end) as [10/4]
from #t group by splb,spm order by splb desc