分別把 計算各自的
1、點擊量/點擊量均值
2、銷售量/銷售量均值
兩者相加,可以得到一個簡單評分
又有問題了,豬肉的評分不應該比五花肉多。
因此我們要加入簡單的權重,譬如點擊量評分佔30%。銷售量評分佔70%
select p_type,p_name, (p_view/view_avg)*0.3+(sales/sales_avg)*0.7 from (
select a.*,b.sales_avg,c. view_avg from (select p_type,a.p_name,a.p_view, IFNULL(b.p_sales,0) as sales from products a
LEFT JOIN products_sales b
on a.p_id=b.p_id
GROUP BY a.p_type,a.p_name order by a.p_type desc, a.p_view desc
) a ,
( select p_type,round(sum(sales)/count(*),0) as sales_avg from ( select p_type, a.p_name,a.p_view, IFNULL(b.p_sales,0) as sales from products a
LEFT JOIN products_sales b
on a.p_id=b.p_id
GROUP BY a.p_type,a.p_name order by a.p_type desc, a.p_view desc ) c
where c.sales>0
GROUP BY p_type
)
b,
(select p_type,round(sum(p_view)/count(*),0) as view_avg from products GROUP BY p_type )
c
where a.p_type=b.p_type and a.p_type=c.p_type ) aa