有表tb, 如下: id value ----------- ----------- 1 aa,bb 2 aaa,bbb,ccc 欲按id,分拆value列, 分拆后结果如下: id value ----------- -------- 1 aa 1 bb 2 aaa 2 bbb 2 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, # B WHERE 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 tb union all select 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 aa 1 bb 2 aaa 2 bbb 2 ccc
原创文章,作者:Maggie-Hunter,如若转载,请注明出处:https://blog.ytso.com/tech/database/267054.html