实现SQL Server中的切割字符串SplitString函数，返回Table

-- =============================================
-- Author:        chenlong
-- Create date: 2015-02-02
-- Description:    根据逗号分隔拆分字符串，返回table
-- =============================================
ALTER FUNCTION [dbo].[fn_SplitString] 
(
    @Input nvarchar(max), --输入字符串
    @Separator nvarchar(max)=',', --分隔符
    @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 the return variable here
    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

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)

Create function [dbo].[f_split](@aString varchar(max),@pattern varchar(10))
returns @temp table(r int,a varchar(100))
--实现split功能 的函数
-- select a from dbo.f_split('我:们a:a:b: ',':')
as
begin
    declare @i int
    declare @row int
    set @row=1
    set @aString=rtrim(ltrim(@aString))
    set @i=charindex(@pattern,@aString)
    while @i>=1
    begin
        insert @temp values(@row,left(@aString,@i-1))
        set @aString=right(@aString,len(@aString)-@i)
        set @i=charindex(@pattern,@aString)
        set @row=@row+1
    end
    if @aString<>''
       insert @temp values(@row,@aString)
    return
end