PHP / MySQL最新照片好友

Question

照片：id，uid，date;

朋友：uid1，uid2，日期，狀態;

我想為用戶的朋友顯示最新照片。 我該怎么辦？

Answer 1

這樣做：

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）;

我認為UID1是用戶而UID2是朋友，這將檢索所有ID