日期:2014-05-18 浏览次数:20599 次
/*
实现行转列
a
name objec score
a EN 89
a CH 78
a HO 99
b EN 34
b CH 88
b HO 66
要求输出结果为:
name EN CH HO
a 89 78 99
b 34 88 66
*/
USE tempdb
IF (SELECT 1 FROM sys.sysobjects WHERE name ='t' AND type='u') is NOT NULL
DROP TABLE t
CREATE TABLE t
(
NAME CHAR(10),
objec CHAR(10),
score FLOAT
)
INSERT INTO t
VALUES('a','EN',89),('a','CH',78),('a','HO',99),('b','EN',34),('b','CH',88),('b','HO',66)
SELECT * FROM T
SELECT NAME ,MAX(CASE objec WHEN 'EN' THEN score ELSE 0 END ) EN,MAX(CASE objec WHEN 'CH' THEN score ELSE 0 END ) CH,MAX(CASE objec WHEN 'HO' THEN score ELSE 0 END ) HO
FROM t
GROUP BY NAME
--=======================================================================================================================================================
/*
实现行转列
a
name objec score
a EN 89
a CH 78
a HO 99
b EN 34
b CH 88
b HO 66
要求输出结果为:
name objec totalsorce
a EN,CH,HO 266
b EN,CH,HO 188
*/
USE tempdb
IF (SELECT 1 FROM sys.sysobjects WHERE name ='t' AND type='u') is NOT NULL
DROP TABLE t
CREATE TABLE t
(
NAME CHAR(10),
objec CHAR(10),
score FLOAT
)
INSERT INTO t
VALUES('a','EN',89),('a','CH',78),('a','HO',99),('b','EN',34),('b','CH',88),('b','HO',66)
SELECT * FROM T
--为了去除objec中的最后一个逗号,插入一个临时表,并使用substring处理
SELECT name ,(SELECT LTRIM(RTRIM(objec))+',' FROM T WHERE objec=t.objec FOR XML PATH('')) objec,SUM(temp.score) totalscroe INTO #tmp
FROM T temp
GROUP BY name
SELECT NAME ,SUBSTRING(objec,0,LEN(objec)-1) objec ,totalscroe
FROM #tmp
------解决方案--------------------
--> 测试数据:[tb]
IF OBJECT_ID('[tb]') IS NOT NULL DROP TABLE [tb]
GO
CREATE TABLE [tb]([czy_id] INT,[type] INT)
INSERT [tb]
SELECT 1,1 UNION ALL
SELECT 1,2 UNION ALL
SELECT 1,2 UNION ALL
SELECT 90,2
GO
--> 测试语句:
SELECT [czy_id],sum(case when [type]=1 then 1 else 0 end) as type1count ,
sum(case when [type]=2 then 1 else 0 end) as type2count
FROM [tb]
group by [czy_id]
/*
czy_id type1count type2count
----------- ----------- -----------
1 1 2
90 0 1
(2 行受影响)
*/