mysql을 사용하여 특정 기간 내의 통계 데이터를 얻는 방법에 대한 튜토리얼

SELECT 
  count(*), 
  DATE_FORMAT(order_info.create_time, '%Y-%m-%d') AS count_by_date 
FROM 
  order_info 
WHERE 
  DATE_FORMAT(order_info.create_time, '%Y') = '2017' 
GROUP BY 
  count_by_date 
ORDER BY NULL

SELECT 
  count(*), 
  DATE_FORMAT(order_info.create_time, '%Y-%m-%d') AS count_by_date 
FROM 
  order_info 
WHERE 
  DATE_FORMAT(order_info.create_time, '%Y-%m') = '2017-04' 
GROUP BY 
  count_by_date 
ORDER BY NULL