mysql - 如何在 MySQL 中不显示负数？

Question

我有这段代码(有效):

SELECT sportsID, newsID, cID, SUM(likes) AS totalLikes 
FROM like_table 
GROUP BY sportsID, newsID 
ORDER BY totalLikes DESC

我试图修改它以不显示负值，但它不起作用。

SELECT sportsID, newsID, cID, SUM(likes) AS totalLikes 
FROM like_table 
WHERE totalLikes > 0 
GROUP BY sportsID, newsID 
ORDER BY totalLikes DESC

有人可以帮忙吗？我不知道我做错了什么。

Answer 1

尝试使用 HAVING 子句:

SELECT sportsID, newsID, cID, SUM(likes) AS totalLikes 
FROM like_table 
GROUP BY sportsID, newsID
HAVING SUM(likes)> 0 
ORDER BY totalLikes DESC

解释:

HAVING 子句被添加到 SQL 中，因为 WHERE 关键字不能与聚合函数一起使用。

WHERE 子句对所选列设置条件，而 HAVING 子句对 GROUP BY 子句创建的组设置条件。