日毎、周毎、月毎集計（MySQL）

１．日毎

group by date(date)

２．周毎
・日曜日開始

group by date(date+ interval 1 - DAYOFWEEK(date) day)

・月曜日開始

group by date(date- interval (5 + DAYOFWEEK(date))%7 day)

３．月毎

group by date(date+ interval 1 - DAYOFMONTH(date) day)

或いは

group by date_format(date, '%Y-%m')

※dateのデータ型はDATETIME

https://qiita.com/ssd710/items/a0dbfe1a6ba1eca278b6