SQL模仿Split 功能

--方法0：动态SQL法
declare @s varchar(100),@sql varchar(1000)
set @s='1,2,3,4,5,6,7,8,9,10'
set @sql='select col='''+ replace(@s,',',''' union all select ''')+''''
PRINT @sql
exec (@sql)

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[f_splitSTR]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[f_splitSTR]
GO
--方法1：循环截取法
CREATE FUNCTION f_splitSTR(
@s   varchar(8000),   --待分拆的字符串
@split varchar(10)     --数据分隔符
)RETURNS @re TABLE(col varchar(100))
AS
BEGIN
DECLARE @splitlen int
SET @splitlen=LEN(@split+'a')-2
WHILE CHARINDEX(@split,@s)>0
BEGIN
  INSERT @re VALUES(LEFT(@s,CHARINDEX(@split,@s)-1))
  SET @s=STUFF(@s,1,CHARINDEX(@split,@s)+@splitlen,'')
END
INSERT @re VALUES(@s)
RETURN
END
GO

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[f_splitSTR]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[f_splitSTR]
GO
--方法2：使用临时性分拆辅助表法
CREATE FUNCTION f_splitSTR(
@s varchar(8000), --待分拆的字符串
@split varchar(10) --数据分隔符
)RETURNS @re TABLE(col varchar(100))
AS
BEGIN
--创建分拆处理的辅助表(用户定义函数中只能操作表变量)
DECLARE @t TABLE(ID int IDENTITY,b bit)
INSERT @t(b) SELECT TOP 8000 0 FROM syscolumns a,syscolumns b

INSERT @re SELECT SUBSTRING(@s,ID,CHARINDEX(@split,@s+@split,ID)-ID)
FROM @t
WHERE ID<=LEN(@s+'a')
AND CHARINDEX(@split,@split+@s,ID)=ID
RETURN
END
GO

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[f_splitSTR]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[f_splitSTR]
GO
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[tb_splitSTR]') and objectproperty(id,N'IsUserTable')=1)
drop table [dbo].[tb_splitSTR]
GO
--方法3：使用永久性分拆辅助表法
--字符串分拆辅助表
SELECT TOP 8000 ID=IDENTITY(int,1,1) INTO dbo.tb_splitSTR
FROM syscolumns a,syscolumns b
GO
--字符串分拆处理函数
CREATE FUNCTION f_splitSTR(
@s     varchar(8000), --待分拆的字符串
@split varchar(10)     --数据分隔符
)RETURNS TABLE
AS
RETURN(
SELECT col=CAST(SUBSTRING(@s,ID,CHARINDEX(@split,@s+@split,ID)-ID) as varchar(100))
FROM tb_splitSTR
WHERE ID<=LEN(@s+'a')
  AND CHARINDEX(@split,@split+@s,ID)=ID)
GO

--方法4：利用sql server2005的OUTER APPLY

CREATE FUNCTION [dbo].[ufn_SplitStringToTable]
(
@str VARCHAR(MAX) ,
@split VARCHAR(10)
)
RETURNS TABLE
    AS
RETURN
    ( SELECT    B.id
      FROM      ( SELECT    [value] = CONVERT(XML , '<v>' + REPLACE(@str , @split , '</v><v>')
                            + '</v>')
                ) A
      OUTER APPLY ( SELECT id = N.v.value('.' , 'varchar(100)')
                    FROM    A.[value].nodes('/v') N ( v )
                  ) B
    )

备注说明：

方法4必须在sql server2005下才可以运行

批注： 以上文章引用于 http://www.cnblogs.com/aierong/archive/2008/11/19/sqlserver_split.html

转载于:https://www.cnblogs.com/-maomao/p/4495183.html

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