有需求，要查询出 A,B 两张表中不重复的数据。例：
A表有数据：a,b,c
B表有数据：b,c,d
查出的结果要： a,d
这个该怎么写呀？？？小弟编程菜鸟求助！
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- SQL code
select col from a where not exists(select 1 from b where col=a.col)union allselect col from b where not exists(select 1 from a where col=b.col)
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--你这个是一列的数据吗？先拆分后，再使用group by having count(1) = 1
- SQL code
/*标题：简单数据拆分(version 2.0)作者：爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开)时间：2010-05-07地点：重庆航天职业学院描述：有表tb, 如下:id value----------- -----------1 aa,bb2 aaa,bbb,ccc欲按id,分拆value列, 分拆后结果如下:id value----------- --------1 aa1 bb2 aaa2 bbb2 ccc*/--1. 旧的解决方法(sql server 2000)create table tb(id int,value varchar(30))insert into tb values(1,'aa,bb')insert into tb values(2,'aaa,bbb,ccc')go--方法1.使用临时表完成SELECT TOP 8000 id = IDENTITY(int, 1, 1) INTO # FROM syscolumns a, syscolumns b SELECT A.id, value = SUBSTRING(A.[value], B.id, CHARINDEX(',', A.[value] + ',', B.id) - B.id)FROM tb A, # BWHERE SUBSTRING(',' + A.[value], B.id, 1) = ','DROP TABLE #--方法2.如果数据量小，可不使用临时表select a.id , value = substring(a.value , b.number , charindex(',' , a.value + ',' , b.number) - b.number) from tb a join master..spt_values b on b.type='p' and b.number between 1 and len(a.value)where substring(',' + a.value , b.number , 1) = ','--2. 新的解决方法(sql server 2005)create table tb(id int,value varchar(30))insert into tb values(1,'aa,bb')insert into tb values(2,'aaa,bbb,ccc')go--方法1.使用xml完成SELECT A.id, B.value FROM( SELECT id, [value] = CONVERT(xml,'<root><v>' + REPLACE([value], ',', '</v><v>') + '</v></root>') FROM tb) A OUTER APPLY( SELECT value = N.v.value('.', 'varchar(100)') FROM A.[value].nodes('/root/v') N(v)) B--方法2.使用CTE完成;with tt as (select id,[value]=cast(left([value],charindex(',',[value]+',')-1) as nvarchar(100)),Split=cast(stuff([value]+',',1,charindex(',',[value]+','),'') as nvarchar(100)) from tbunion allselect id,[value]=cast(left(Split,charindex(',',Split)-1) as nvarchar(100)),Split= cast(stuff(Split,1,charindex(',',Split),'') as nvarchar(100)) from tt where split>'')select id,[value] from tt order by id option (MAXRECURSION 0)DROP TABLE tb/*id value----------- ------------------------------1 aa1 bb2 aaa2 bbb2 ccc(5 行受影响)*/
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- SQL code
create table taba(id varchar(20))create table tabb(id varchar(20))insert into taba values('A,B,C')insert into tabb values('B,C');with t as(select substring(','+a.id,c.number+1,charindex(',',a.id+',',c.number)-c.number) idfrom taba a inner join master.dbo.spt_values con c.[type]='P' and substring(','+a.id,c.number,1)=',') select id from twhere charindex(t.id,(select top 1 id from tabb))=0id---------------------A(1 row(s) affected)