mysql排序發送和接收的消息

Question

我的數據庫中有一個表

SenderId    ReceiverId  Message         DateAndTime
int(11)     int(11)     varchar(200)    DATETIME

我想以對話形式對登錄用戶的所有消息進行排序。 登錄的用戶之間的消息說UserA和UserB，UserC應該顯示如下：

UserA   UserB   Sent
UserA   UserB   Sent
UserB   UserA   Received

UserA   UserC   Sent
UserC   UserA   Received
UserA   UserC   Sent

UserD   UserA   Receied
UserA   UserD   Sent

我已經嘗試過此查詢，但結果與我預期的不同

SELECT * FROM messages WHERE SenderId like ? or ReceiverId like ? order by senderId, dateAndDate;

Answer 1

這可能有效。 它不會按時間對會話進行排序，而是按參與者進行排序。

SELECT CONCAT(LEAST(SenderID, ReceiverId), '-', GREATEST(SenderID, ReceiverId)) AS conversation
  , SenderID, ReceiverID, Message, DateAndTime
FROM messages
WHERE SenderID = ? OR ReceiverId =?
ORDER BY conversation, DateAndTime DESC;

Answer 2

這應該可以解決問題。

SELECT SenderId, ReceiverId, Message, DateAndTime, CASE WHEN SenderId=1 THEN ReceiverId Else SenderId END as Optional from messages where SenderId = 1 or ReceiverId=1 order by Optional, DateAndTime desc;

假設Logged UserID為1，請改用占位符。