[MSSQL]实现SQL Server中的切割字符串SplitString标量函数

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

/*
by kudychen 2011-9-28
*/
CREATE function [dbo].[SplitString]
(
@Input nvarchar(max), --input string to be separated
@Separator nvarchar(max)=',', --a string that delimit the substrings in the input string
@RemoveEmptyEntries bit=1 --the return value does not include array elements that contain an empty string
)
returns @TABLE table
(
[Id] int identity(1,1),
[Value] nvarchar(max)
)
as
begin
declare @Index int, @Entry nvarchar(max)
set @Index = charindex(@Separator,@Input)

while (@Index>0)
begin
set @Entry=ltrim(rtrim(substring(@Input, 1, @Index-1)))

if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>'')
begin
insert into @TABLE([Value]) Values(@Entry)
end

set @Input = substring(@Input, @Index+datalength(@Separator)/2, len(@Input))
set @Index = charindex(@Separator, @Input)
end

set @Entry=ltrim(rtrim(@Input))
if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>'')
begin
insert into @TABLE([Value]) Values(@Entry)
end

return
end

如何使用：

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)