此查询有误（每日每月销售额）

Question

SELECT s.id
     , s.qty
     , s.price
     , s.date
     , p.name 
  FROM sales s 
  LEFT 
  JOIN products p 
    ON s.product_id = p.id
 ORDER 
    BY s.date DESC 
 LIMIT 5

function find_sale_by_dates($start_date,$end_date){   global $db;   
$start_date  = date("Y-m-d", strtotime($start_date));   
$end_date = date("Y-m-d", strtotime($end_date));   
$sql  = "
SELECT s.date
     , p.name
     , p.sale_price
     , p.buy_price
     , COUNT(s.product_id) total_records
     , SUM(s.qty) total_sales
     , SUM(p.sale_price * s.qty) total_saleing_price
     , SUM(p.buy_price * s.qty) total_buying_price
  FROM sales s
  LEFT 
  JOIN products p 
    ON s.product_id = p.id
 WHERE s.date BETWEEN '$start_date' AND '$end_date'
 GROUP 
    BY DATE(s.date)
     , p.name
 ORDER
    BY DATE(s.date) DESC
 ";   return $db->query($sql);

 }