写自己需要的SQL function

 1 SET ANSI_NULLS ON
 2 GO
 3 SET QUOTED_IDENTIFIER ON
 4 GO
 5 
 6 CREATE function [dbo].[SplitString]
 7 (
 8     @Input nvarchar(max),    --要分割的字符串
　　　　@Separator nvarchar(max)=‘,‘, --分隔符，可以是一个字符也可以是多个字符
 9     @RemoveEmptyEntries bit=1 ) --是否移除空字符串
10 returns @TABLE table --返回一个存放已经分割好的字符串的table
11 (
12     [Id] int identity(1,1),
13     [Value] nvarchar(max)
14 ) 
15 as
16 begin 
17     declare @Index int, @Entry nvarchar(max)
18     set @Index = charindex(@Separator,@Input)
19 
20     while (@Index>0)
21     begin
22         set @Entry=ltrim(rtrim(substring(@Input, 1, @Index-1)))
23         
24         if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>‘‘)
25             begin
26                 insert into @TABLE([Value]) Values(@Entry)
27             end
28 
29         set @Input = substring(@Input, @Index+datalength(@Separator)/2, len(@Input))
30         set @Index = charindex(@Separator, @Input)
31     end
32     
33     set @Entry=ltrim(rtrim(@Input))
34     if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>‘‘)
35         begin
36             insert into @TABLE([Value]) Values(@Entry)
37         end
38 
39     return
40 end

declare @str1 varchar(max), @str2 varchar(max), @str3 varchar(max)

set @str1 = ‘1,2,3‘
set @str2 = ‘1###2###3‘
set @str3 = ‘1###2###3###‘

select [Value] from [dbo].[SplitString](@str1, ‘,‘, 1)
select [Value] from [dbo].[SplitString](@str2, ‘###‘, 1)
select [Value] from [dbo].[SplitString](@str3, ‘###‘, 0)