我有一个问题,当做一个JOIN的两个表和过滤使用HAVING这两个表。Mysql加入,总和,拥有,分组依据。无法解决
假定我的表是这样的:
产品:
id | Name
1 | Product 1
2 | Product 2
3 | Product 3
点评:
Name | Product_id | score
Review 1 | 1 | 10000
我最好的猜测是下面的,但它不工作:
SELECT "products".*, sum("reviews".score) FROM "products" INNER JOIN "reviews" ON "reviews"."empire_id" = "products"."id" GROUP BY products.id HAVING sum("reviews".score)=0;
我想获得得分为0的产品,这意味着它们尚未经过评审。我觉得这应该很容易,但我似乎无法弄清楚。
您帮我理解了它出来了! 由于 SELECT products.id,products.name,总和( “评论” .score) FROM产品 LEFT JOIN评论ON reviews.product_id = products.id GROUP BY products.id,products.name HAVING SUM(“reviews”.SCORE)是NULL; – 2012-02-28 00:50:37