mysql分组问题

Question

有表sub_item,   数据如下：   
  id         title                     type   
  1             abddcd                 组一   
  2             adfasdd               组一   
  3             gdadadd               组二   
  4             ewgdds                 组二   
  5             hsdfgsf               组三   
  6             hadewe                 组四   
  7             ghadewe               组四   
  8             hadewe                 组四   
    
  select   所有数据，要求如下按组显示：   
  组一有：   
  abddcd     adfasdd   
  组二有：   
  gdadadd   
  .....   
  组四有:   
  hadewe     ghadewe       hadewe       

Answer 1

select type,GROUP_CONCAT(title) from sub_item group by type

Answer 2

create function f_str(@str)
as
declare @i char(2000)
select @i = @i + @str from tb group by type

Answer 3

select group_concat(`title` separator ' '),`type` from sub_item group by `type`;