實現SQL Server中的切割字符串SplitString函數

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)

執行結果：

裡面還有個自增的[Id]字段哦，在某些情況下有可能會用上的，例如根據Id來保存排序等等。

例如根據某表的ID保存排序：

    update a set a.[Order]=t.[Id]
        from [dbo].[表] as a join [dbo].SplitString('1,2,3', ',', 1) as t on a.[Id]=t.[Value]

具體的應用請根據自己的情況來吧。