sql中比较一个字符串中是否含有另一个字符串中的一个字符的实现代码,需要的朋友可以参考下。
版本一:按分隔符进行比较算法思路:按分隔符截取搜索字符串循环与待搜索字符进行比较
代码如下:
USE [Fly]
GO
--参数:@inStr 待搜索字串,@fndStr 搜索字串,@doc 分隔符
-- 例:select dbo.fSearch('1,2,3,4,5,6','3,6,5,8,2',',') 返回0-不匹配,返回1-匹配(@instr中有@fndStr内容)
--可以用于表搜索,如:
-- Select *,dbo.fSearch(str,'3,6,5,8,2',',') as 是否匹配 from 表名
-- @fndStr和@doc两个参数就需要你自己提供了,@inStr可以是数据表里的某个待搜索字段名
CREATE FUNCTION CGF_FN_Search(@inStr VARCHAR(500),@fndStr VARCHAR(500),@doc VARCHAR(5))
RETURNS INT
AS
BEGIN
DECLARE @i INT,@c VARCHAR(500),@fStr VARCHAR(500)
SET @fStr = @fndStr
WHILE(LEN(@fStr) > 0)
BEGIN
SET @i = Charindex(@doc, @fStr)
IF(@i = 0)
BEGIN
IF(CHARINDEX(@fStr,@inStr) > 0)
RETURN 1
ELSE
RETURN 0
END
ELSE
BEGIN
SET @c = SUBSTRING(@fStr,1,@i-1)
IF(CHARINDEX(@c,@inStr) > 0)
RETURN 1
ELSE
SET @fStr = SUBSTRING(@fStr,@i+LEN(@doc),LEN(@fStr))
END
END
RETURN 0
END
版本二:逐字进行比较
算法思路:逐字截取搜索字符串循环与待搜索字符进行比较
代码如下:
USE [Fly]
GO
/****** Object: UserDefinedFunction [dbo].[CGF_FN_SearchChar] Script Date: 09/03/2010 16:42:12 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[CGF_FN_SearchChar](@inStr VARCHAR(500),@fndStr VARCHAR(500))
RETURNS INT
AS
BEGIN
DECLARE @i INT,@f INT,@c VARCHAR(1)
SET @i = 1
SET @f = LEN(@fndStr)
WHILE(@i BEGIN
SET @c = SUBSTRING(@fndStr, @i, @i)
IF(CHARINDEX(@c,@inStr) > 0)
BEGIN
RETURN 1
END
SET @i = @i + 1
END
RETURN 0
END

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