Oracle的數(shù)據(jù)表中行轉(zhuǎn)列與列轉(zhuǎn)行的操作實例講解
行轉(zhuǎn)列
一張表

查詢結(jié)果為

--行轉(zhuǎn)列
select years,(select amount from Tb_Amount as A where month=1 and A.years=Tb_Amount.years)as m1, (select amount from Tb_Amount as A where month=2 and A.years=Tb_Amount.years)as m2, (select amount from Tb_Amount as A where month=3 and A.years=Tb_Amount.years)as m3 from Tb_Amount group by years
或者為
select years as 年份, sum(case when month='1' then amount end) as 一月, sum(case when month='2' then amount end) as 二月, sum(case when month='3' then amount end) as 三月 from dbo.Tb_Amount group by years order by years desc
2.人員信息表包括姓名 時代 金額

顯示行轉(zhuǎn)列
姓名 時代 金額
姓名 年輕 中年 老年
張麗 1000000.00 4000000.00 500000000.00
孫子 2000000.00 12233335.00 4552220010.00

select uname as 姓名, SUM(case when era='年輕' then amount end) as 年輕, SUM(case when era='中年' then amount end) as 中年, SUM(case when era='老年' then amount end) as 老年 from Tb_People group by uname order by uname desc
3.學(xué)生表 [Tb_Student]

顯示效果

靜態(tài)SQL,指subject只有語文、數(shù)學(xué)、英語這三門課程。
select sname as 姓名, max(case Subject when '語文' then grade else 0 end) as 語文, max(case Subject when '數(shù)學(xué)' then grade else 0 end) as 數(shù)學(xué), max(case Subject when '英語' then grade else 0 end) as 英語 from dbo.Tb_Student group by sname order by sname desc
--動態(tài)SQL,指subject不止語文、數(shù)學(xué)、英語這三門課程。
declare @sql varchar(8000) set @sql = 'select sname as ' + '姓名' select @sql = @sql + ' , max(case Subject when ''' + Subject + ''' then grade else 0 end) [' + Subject + ']' from (select distinct Subject from Tb_Student) as a set @sql = @sql + ' from Tb_Student group by sname order by sname desc' exec(@sql)
oracle中Decode()函數(shù)使用 然后將這些累計求和(sum部分)
select t.sname AS 姓名, sum(decode(t.subject,'語文',grade,null))語文 , sum(decode(t.subject,'數(shù)學(xué)',grade,null)) 數(shù)學(xué), sum(decode(t.subject,'英語',grade,null)) 英語 from Tb_Student t group by sname order by sname desc
列轉(zhuǎn)行

生成

sql代碼
生成靜態(tài):
select *
from (select sname,[Course ] ='數(shù)學(xué)',[Score]=[數(shù)學(xué)] from Tb_students union all
select sname,[Course]='英語',[Score]=[英語] from Tb_students union all
select sname,[Course]='語文',[Score]=[語文] from Tb_students)t
order by sname,case [Course] when '語文' then 1 when '數(shù)學(xué)' then 2 when '英語' then 3 end
go
--列轉(zhuǎn)行的靜態(tài)方案:UNPIVOT,sql2005及以后版本
SELECT sname,Subject, grade
from dbo.Tb_students
unpivot(grade for Subject in([語文],[數(shù)學(xué)],[英語]))as up
GO
--列轉(zhuǎn)行的動態(tài)方案:UNPIVOT,sql2005及以后版本
--因為行是動態(tài)所以這里就從INFORMATION_SCHEMA.COLUMNS視圖中獲取列來構(gòu)造行,同樣也使用了XML處理。
declare @s nvarchar(4000)
select @s=isnull(@s+',','')+quotename(Name)
from syscolumns where ID=object_id('Tb_students') and Name not in('sname')
order by Colid
exec('select sname,[Subject],[grade] from Tb_students unpivot ([grade] for [Subject] in('+@s+'))b')
go
select
sname,[Subject],[grade]
from
Tb_students
unpivot
([grade] for [Subject] in([數(shù)學(xué)],[英語],[語文]))b
相關(guān)文章
Oracle和MySQL的數(shù)據(jù)導(dǎo)入為何差別這么大
這篇文章主要介紹了Oracle和MySQL的數(shù)據(jù)導(dǎo)入有哪些區(qū)別,幫助大家更好的理解和學(xué)習(xí),感興趣的朋友可以了解下2020-08-08
oracle 數(shù)據(jù)按主鍵刪除慢問題的解決方法
下面小編就為大家?guī)硪黄猳racle 數(shù)據(jù)按主鍵刪除慢問題的解決方法。小編覺得挺不錯的,現(xiàn)在就分享給大家,也給大家做個參考。一起跟隨小編過來看看吧2016-10-10
Linux下啟動Oracle服務(wù)和監(jiān)聽程序步驟
這篇文章給大家介紹了Linux下啟動Oracle服務(wù)和監(jiān)聽程序步驟,在文章末尾給大家介紹了Oracle數(shù)據(jù)庫的啟動和關(guān)閉方式小結(jié),感興趣的朋友一起看看吧2017-08-08
win x64下安裝oracle 12c出現(xiàn)INS-30131報錯的解決方法
這篇文章主要介紹了win x64下安裝oracle 12c出現(xiàn)INS-30131報錯的解決方法,感興趣的小伙伴們可以參考一下2016-07-07

