在特定月份按周获取所有记录

I want to fetch data weekwise for the particular month.

ex: if i select may month . i need count of first week,count of second week ,count of third week and so on

use the following query.

select
      concat(year(date_format(timefield, '%Y-%m-%d')), ' week ', substring_index(dayofyear(date_format(timefiels, '%Y-%m-%d'))/7+1, '.', 1)) as time,
      sum(sales) as sales 
 from 
      account 
where 
      timefield>='2014-05-01 00:00:00' 
  and timefield<='2014-05-31 23:59:59'

group by
          time;