MySQL将数据按周聚合（自定义周的起始日）

$week_start = 0   // 0- 6: 周日-周六
SELECT: 

week_start=0:

CONCAT_WS('~', subdate(Fdate,date_format(Fdate,'%w')-$week_start), subdate(Fdate,date_format(Fdate,'%w')-$week_end) )

week_start=1-6:

CONCAT_WS('~', subdate(Fdate, if(date_format(Fdate, '%w')<$week_start,date_format(Fdate, '%w')+7-$week_start,date_format(Fdate,'%w')-$week_start)),
	subdate(Fdate, if(date_format(Fdate, '%w')<$week_start,date_format(Fdate,'%w')+7-$week_end,date_format(Fdate,'%w')-$week_end )) )






GROUP BY:

yearweek(Fdate, $week_start)