PHP/MySQL 最新照片啦

Question

照片：id、uid、日期；

好友：uid1、uid2、日期、状态；

我想向用户的朋友展示最新的照片。我该怎么办？

Answer 1

这将做到这一点：

SELECT p.id
FROM Photos AS p, Friends AS f
WHERE p.uid = f.uid2 AND f.uid1 = ${userX.id}
ORDER BY p.date DESC
LIMIT 1;

Answer 2

SELECT id FROM photos WHERE uid IN (SELECT uid2 FROM Friends WHERE uid1 = {$uid1} ORDER BY date DESC LIMIT 1);

我假设 UID1 是用户，UID2 是朋友，这将检索所有 ID