php - PHP/MySQL 消息系统

Question

嗨，我正在尝试使用 php 和 mysql 制作一个消息系统。

mysql表很简单:ID发件人接收者文本时间戳

我试图让消息传递有点像 Facebook/Twitter，因此列表位于“对话”中，并且可以查看对话中的最后一条消息。

这是我的自动取款机:

(SELECT * FROM messages WHERE receiver = 13 OR sender = 13 GROUP BY receiver,sender ORDER BY id ASC) ORDER BY id ASC

Answer 1

SELECT messages.* FROM messages, (SELECT MAX(id) as lastid FROM messages 
WHERE receiver = 13 OR sender = 13 
GROUP BY CONCAT(LEAST(receiver,sender),'.',GREATEST(receiver,sender))) as conversations
WHERE id = conversations.lastid
ORDER BY timestamp DESC

您需要的是聊天伙伴之间的唯一对话 ID。我已经用子查询模拟了这个，希望这有帮助