本文章是一篇讲述利用mssql来提取字符串中的所有数字，英文，中文，过滤重复字符实例，有需要的朋友参考一下吧。
 代码如下 复制代码
if object_id('dbo.get_number') is not null
drop function dbo.get_number
go
create function dbo.get_number(@s varchar(100))
returns varchar(100)
as
begin
while patindex('%[^0-9]%',@s) > 0
begin
set @s=stuff(@s,patindex('%[^0-9]%',@s),1,'')
end
return @s
end
go
--测试
print dbo.get_number('呵呵abc-12,3abc')
go
--123
--------------------------------------------------------------------
--提取英文
if object_id('dbo.get_str') is not null
drop function dbo.get_str
go
create function dbo.get_str(@s varchar(100))
returns varchar(100)
as
begin
while patindex('%[^a-z]%',@s) > 0
begin
set @s=stuff(@s,patindex('%[^a-z]%',@s),1,'')
end
return @s
end
go
--测试
print dbo.get_str('呵呵abc123abc')
go
--------------------------------------------------------------------
--提取中文
if object_id('dbo.china_str') is not null
drop function dbo.china_str
go
create function dbo.china_str(@s nvarchar(100))
returns varchar(100)
as
begin
while patindex('%[^吖-座]%',@s) > 0
set @s = stuff(@s,patindex('%[^吖-座]%',@s),1,n'')
return @s
end
go
print dbo.china_str('呵呵abc123abc')
go
--------------------------------------------------------------------
--过滤重复字符
if object_id('dbo.distinct_str') is not null
drop function dbo.distinct_str
go
create function dbo.distinct_str(@s nvarchar(100),@split varchar(50))
returns varchar(100)
as
begin
if @s is null return(null)
declare @new varchar(50),@index int,@temp varchar(50)
if left(@s,1)@split
set @s = @split+@s
if right(@s,1)@split
set @s = @s+@split
while charindex(@split,@s)>0 and len(@s)1
begin
set @index = charindex(@split,@s)
set @temp = left(@s,charindex(@split,@s,@index+len(@split)))
if @new is null
set @new = isnull(@new,'')+@temp
else
set @new = isnull(@new,'')+replace(@temp,@split,'')+@split
while charindex(@temp,@s)>0
begin
set @s=stuff(@s,charindex(@temp,@s)+len(@split),charindex(@split,@s,charindex(@temp,@s)+len(@split))-charindex(@temp,@s),'')
end
end
return right(left(@new,len(@new)-1),len(left(@new,len(@new)-1))-1)
end
go
print dbo.distinct_str('a,a,b,c,c,b,c,',',')
--a,b,c
go
--------------------------------------------------------------------
--过滤重复字符2
if object_id('dbo.distinct_str2') is not null
drop function dbo.distinct_str2
go
create function dbo.distinct_str2(@s varchar(8000))
returns varchar(100)
as
begin
if @s is null return(null)
declare @new varchar(50),@index int,@temp varchar(50)
while len(@s)>0
begin
set @new=isnull(@new,'')+left(@s,1)
set @s=replace(@s,left(@s,1),'')
end
return @new
end
go
select dbo.distinct_str2('aabccd')
--abcd
go
--------------------------------------------------------------------
if object_id('dbo.split_str') is not null
drop function dbo.split_str
go
create function dbo.split_str(
@s varchar(8000),      --包含多个数据项的字符串
@index int,             --要获取的数据项的位置
@split varchar(10)     --数据分隔符
)
returns varchar(100)
as
begin
if @s is null return(null)
declare @splitlen int
select @splitlen=len(@split+'a')-2
while @index>1 and charindex(@split,@s+@split)>0
select @index=@index-1,@s=stuff(@s,1,charindex(@split,@s+@split)+@splitlen,'')
return(isnull(left(@s,charindex(@split,@s+@split)-1),''))
end
go
print dbo.split_str('aa|bb|cc',2,'|')
--
go