感觉比较复杂的数据合并与去重,高手们看看如何解决?
有一个表
url aurl telmemo
www.baidu.combaidu.com123ok
mi.baidu.combaidu.com456NO
mp3.baidu.combaidu.com888mp3
我想把aurl想同的记录,,tel的值得和memo的值,,合并到url含www的www.baidu.com这条上,然后只保留www.baidu.com这一条记录。
何留后的结果为
url aurl tel memo
www.baidu.combaidu.com 123,456,888ok,no,mp3
请问用sql如何时实现,可以多条命令,只要能实现这个功能就OK。。
[解决办法]
表a name num aa 1 bb 2 cc 4 dd 4 ee 2 一条语句实现如下:name aa,bb,cc,dd,ee DECLARE @STR VARCHAR(8000)SELECT @STR=ISNULL(@STR+',','')+name FROM (SELECT DISTINCT NAME FROM A)AS TSELECT @STR问题描述:无论是在sql 2000,还是在sql 2005 中,都没有提供字符串的聚合函数, 所以,当我们在处理下列要求时,会比较麻烦:有表tb, 如下:id value1 aa1 bb2 aaa2 bbb2 ccc需要得到结果:id values1 aa,bb2 aaa,bbb,ccc即,group by id, 求value 的和(字符串相加)1. 旧的解决方法-- 1. 创建处理函数CREATE FUNCTION dbo.f_str(@id int)RETURNS varchar(8000)ASBEGIN DECLARE @r varchar(8000) SET @r = '' SELECT @r = @r + ',' + value FROM tb WHERE id=@id RETURN STUFF(@r, 1, 1, '')ENDGO-- 调用函数SELECt id, values=dbo.f_str(id) FROM tb GROUP BY id-- 2. 新的解决方法-- 示例数据DECLARE @t TABLE(id int, value varchar(10))INSERT @t SELECT 1, 'aa'UNION ALL SELECT 1, 'bb'UNION ALL SELECT 2, 'aaa'UNION ALL SELECT 2, 'bbb'UNION ALL SELECT 2, 'ccc'-- 查询处理SELECT *FROM (SELECT DISTINCT Id FROM @t)AOUTER APPLY( SELECT [values]= STUFF(REPLACE(REPLACE( ( SELECT value FROM @t N WHERE id = A.id FOR XML AUTO ), '<N value="', ','), '"/>', ''), 1, 1, ''))N/*--结果id values----------- ----------------1 aa,bb2 aaa,bbb,ccc(2 行受影响)--*/--各种字符串分函数--3.3.1 使用游标法进行字符串合并处理的示例。--处理的数据CREATE TABLE tb(col1 varchar(10),col2 int)INSERT tb SELECT 'a',1UNION ALL SELECT 'a',2UNION ALL SELECT 'b',1UNION ALL SELECT 'b',2UNION ALL SELECT 'b',3--合并处理--定义结果集表变量DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))--定义游标并进行合并处理DECLARE tb CURSOR LOCALFORSELECT col1,col2 FROM tb ORDER BY col1,col2DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100)OPEN tbFETCH tb INTO @col1,@col2SELECT @col1_old=@col1,@s=''WHILE @@FETCH_STATUS=0BEGIN IF @col1=@col1_old SELECT @s=@s+','+CAST(@col2 as varchar) ELSE BEGIN INSERT @t VALUES(@col1_old,STUFF(@s,1,1,'')) SELECT @s=','+CAST(@col2 as varchar),@col1_old=@col1 END FETCH tb INTO @col1,@col2ENDINSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))CLOSE tbDEALLOCATE tb--显示结果并删除测试数据SELECT * FROM @tDROP TABLE tb/*--结果col1 col2a 1,2b 1,2,3--*/GO--3.3.2 使用用户定义函数,配合SELECT处理完成字符串合并处理的示例--处理的数据CREATE TABLE tb(col1 varchar(10),col2 int)INSERT tb SELECT 'a',1UNION ALL SELECT 'a',2UNION ALL SELECT 'b',1UNION ALL SELECT 'b',2UNION ALL SELECT 'b',3GO--合并处理函数CREATE FUNCTION dbo.f_str(@col1 varchar(10))RETURNS varchar(100)ASBEGIN DECLARE @re varchar(100) SET @re='' SELECT @re=@re+','+CAST(col2 as varchar) FROM tb WHERE col1=@col1 RETURN(STUFF(@re,1,1,''))ENDGO--调用函数SELECT col1,col2=dbo.f_str(col1) FROM tb GROUP BY col1--删除测试DROP TABLE tbDROP FUNCTION f_str/*--结果col1 col2a 1,2b 1,2,3--*/GO--3.3.3 使用临时表实现字符串合并处理的示例--处理的数据CREATE TABLE tb(col1 varchar(10),col2 int)INSERT tb SELECT 'a',1UNION ALL SELECT 'a',2UNION ALL SELECT 'b',1UNION ALL SELECT 'b',2UNION ALL SELECT 'b',3--合并处理SELECT col1,col2=CAST(col2 as varchar(100)) INTO #t FROM tbORDER BY col1,col2DECLARE @col1 varchar(10),@col2 varchar(100)UPDATE #t SET @col2=CASE WHEN @col1=col1 THEN @col2+','+col2 ELSE col2 END, @col1=col1, col2=@col2SELECT * FROM #t/*--更新处理后的临时表col1 col2a 1a 1,2b 1b 1,2b 1,2,3--*/--得到最终结果SELECT col1,col2=MAX(col2) FROM #t GROUP BY col1/*--结果col1 col2a 1,2b 1,2,3--*/--删除测试DROP TABLE tb,#tGO--3.3.4.1 每组<=2 条记录的合并--处理的数据CREATE TABLE tb(col1 varchar(10),col2 int)INSERT tb SELECT 'a',1UNION ALL SELECT 'a',2UNION ALL SELECT 'b',1UNION ALL SELECT 'b',2UNION ALL SELECT 'c',3--合并处理SELECT col1, col2=CAST(MIN(col2) as varchar) +CASE WHEN COUNT(*)=1 THEN '' ELSE ','+CAST(MAX(col2) as varchar) ENDFROM tbGROUP BY col1DROP TABLE tb/*--结果col1 col2 ---------- ----------a 1,2b 1,2c 3--*/--3.3.4.2 每组<=3 条记录的合并--处理的数据CREATE TABLE tb(col1 varchar(10),col2 int)INSERT tb SELECT 'a',1UNION ALL SELECT 'a',2UNION ALL SELECT 'b',1UNION ALL SELECT 'b',2UNION ALL SELECT 'b',3UNION ALL SELECT 'c',3--合并处理SELECT col1, col2=CAST(MIN(col2) as varchar) +CASE WHEN COUNT(*)=3 THEN ',' +CAST((SELECT col2 FROM tb WHERE col1=a.col1 AND col2 NOT IN(MAX(a.col2),MIN(a.col2))) as varchar) ELSE '' END +CASE WHEN COUNT(*)>=2 THEN ','+CAST(MAX(col2) as varchar) ELSE '' ENDFROM tb aGROUP BY col1DROP TABLE tb/*--结果col1 col2---------- ------------a 1,2b 1,2,3c 3--*/GOif not object_id('A') is null drop table AGoCreate table A([id] int,[cname] nvarchar(2))Insert Aselect 1,N'张三' union allselect 2,N'李四' union allselect 3,N'王五' union allselect 4,N'蔡六'Go--> --> if not object_id('B') is null drop table BGoCreate table B([id] int,[cname] nvarchar(5))Insert Bselect 1,N'1,2,3' union allselect 2,N'3,4'Gocreate function F_str(@cname nvarchar(100))returns nvarchar(100)asbegin select @cname=replace(@cname,ID,[cname]) from A where patindex('%,'+rtrim(ID)+',%',','+@cname+',')>0return @cnameendgoselect [id],dbo.F_str([cname])[cname] from Bid cname1 张三,李四,王五2 王五,蔡六(2 個資料列受到影響)我现在有一字段值为:a,b,c 分隔符为逗号. 我现在想实现目地值为: 字段: id name 1 a 2 b 3 c 在SQL中咋实现呢?declare @str varchar(8000) set @str = 'a1,b1,c2,d1,e3,f5' set @str = 'select name='''+replace(@str,',',''''+' union all select ''')+'''' set @str='select id=identity(int,1,1),name into #temp from ('+@str+') a select * from #temp drop table #temp'exec(@str)--参考:CREATE TABLE TB(ID VARCHAR(6), COLOR NVARCHAR(30))INSERT TBSELECT '173160', N'#特深蓝色,#特深蓝色' UNION ALL SELECT '173160', N'#特深蓝色,#特深蓝色' UNION ALL SELECT '911169', N'#宝蓝色,#宝蓝色,#花灰色,#花灰色' UNION ALL SELECT '911169', N'#宝蓝色,#宝蓝色,#花灰色,#花灰色' UNION ALL SELECT '911169', N'#宝蓝色,#宝蓝色,#花灰色,#花灰色' UNION ALL SELECT '911169', N'#宝蓝色,#宝蓝色,#花灰色,#花灰色'GOCREATE FUNCTION F_getStr(@color nvarchar(30))returns nvarchar(30)asbegin declare @str nvarchar(30),@temp nvarchar(30) set @str='' set @temp='' while charindex(',', @color+',')>0 begin set @temp=left(@color, charindex(',', @color+',')-1) if charindex(','+@temp+',', ','+@str+',')=0 set @str=@str+','+@temp set @color=stuff(@color, 1, charindex(',', @color+','), '') end return stuff(@str, 1, 1, '')endgoSELECT ID,dbo.F_getStr(COLOR) as COLOR FROM TBDROP TABLE TBDROP FUNCTION F_getStr/*ID COLOR173160 #特深蓝色173160 #特深蓝色911169 #宝蓝色,#花灰色911169 #宝蓝色,#花灰色911169 #宝蓝色,#花灰色911169 #宝蓝色,#花灰色*/
[解决办法]