17.各种字符串分拆处理函数

--各种字符串分函数

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

--3.2.1 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

--3.2.3.1 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

--3.2.3.2 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


/*==============================================*/

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

--3.2.5 将数据项按数字与非数字再次拆份
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(No varchar(100),Value varchar(20))
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	No=REVERSE(STUFF(col,1,PATINDEX('%[^-^.^0-9]%',col+'a')-1,'')),
		Value=REVERSE(LEFT(col,PATINDEX('%[^-^.^0-9]%',col+'a')-1))
	FROM(
		SELECT col=REVERSE(SUBSTRING(@s,ID,CHARINDEX(@split,@s+@split,ID)-ID))
		FROM @t
		WHERE ID<=LEN(@s+'a') 
			AND CHARINDEX(@split,@split+@s,ID)=ID)a
	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

--3.2.6 分拆短信数据
CREATE FUNCTION f_splitSTR(@s varchar(8000))
RETURNS @re TABLE(split varchar(10),value varchar(100))
AS
BEGIN
	DECLARE @splits TABLE(split varchar(10),splitlen as LEN(split))
	INSERT @splits(split)
	SELECT 'AC' UNION ALL
	SELECT 'BC' UNION ALL
	SELECT 'CC' UNION ALL
	SELECT 'DC'	
	DECLARE @pos1 int,@pos2 int,@split varchar(10),@splitlen int
	SELECT TOP 1 
		@pos1=1,@split=split,@splitlen=splitlen
	FROM @splits
	WHERE @s LIKE split+'%'
	WHILE @pos1>0
	BEGIN
		SELECT TOP 1
			@pos2=CHARINDEX(split,@s,@splitlen+1)
		FROM @splits
		WHERE CHARINDEX(split,@s,@splitlen+1)>0
		ORDER BY CHARINDEX(split,@s,@splitlen+1)
		IF @@ROWCOUNT=0
		BEGIN
			INSERT @re VALUES(@split,STUFF(@s,1,@splitlen,''))
			RETURN
		END
		ELSE
		BEGIN
			INSERT @re VALUES(@split,SUBSTRING(@s,@splitlen+1,@pos2-@splitlen-1))
			SELECT TOP 1 
				@pos1=1,@split=split,@splitlen=splitlen,@s=STUFF(@s,1,@pos2-1,'')
			FROM @splits
			WHERE STUFF(@s,1,@pos2-1,'') LIKE split+'%'
		END
	END
	RETURN
END
GO