sql怎么分割字段的一串数字

sql如何分割字段的一串数字？


比如我表A里有个字段B，数据为1234，



要的就是一段sql 查询出表A中B字段结果为 1，2，3，4


[解决办法]

SQL code

alter function fn_getStr(@v int)returns varchar(32)begin    declare @retValue varchar(32)    set @retValue =''    if (@v is not null)        begin                declare @s varchar(16),                                @l tinyint,                @i tinyint        set @i = 1        set @s =convert(varchar(16),@v)        set @l = len(@s)        while(@i<=@l)        begin            set @retValue = @retValue + substring(@s,@i,1)+','            --print @retValue            set @i = @i + 1        end    end    return left(@retValue,len(@retValue)-1)endselect dbo.fn_getStr(123)--------------------------------1,2,3,4(1 行受影响)
[解决办法]
SQL code
--> 测试数据: #tbif object_id('tempdb.dbo.#tb') is not null drop table #tbcreate table #tb ([val] varchar(10))set nocount oninsert into #tbselect '1234'declare @Num table(id int)insert into @Num select number from master..spt_values where number between 1 and 100 and type='p'set nocount offdeclare @str varchar(100)select @str=isnull(@str+','+element,element) from (select SUBSTRING(val,id,1) element from #tb a join @Num b on SUBSTRING(val,id,1)<>'') as T print(@str)--结果/*1,2,3,4*/