sqlserver中遍历字符串的sql语句

declare @ddd varchar(50),@split varchar(1)

set @ddd = 12345678,1234567890,1234567890,123456,123456789

set @split = ,
while(charindex(@split,@ddd)<>0)
begin
select substring(@ddd,1,charindex(@split,@ddd)-1)
set @ddd = stuff(@ddd,1,charindex(@split,@ddd),)
select @ddd
end