MySQL创建聊天记录表实现在线聊天功能

CREATE TABLE chat_messages (
    id INT AUTO_INCREMENT PRIMARY KEY,
    sender_id INT NOT NULL,
    receiver_id INT NOT NULL,
    message TEXT NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "chat_app";

// 创建数据库连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 示例插入聊天记录
$senderId = 1; // 发送者的用户ID
$receiverId = 2; // 接收者的用户ID
$message = "你好，这是一条示例消息。"; // 消息内容

$sql = "INSERT INTO chat_messages (sender_id, receiver_id, message) VALUES ($senderId, $receiverId, '$message')";

if ($conn->query($sql) === TRUE) {
    echo "新纪录插入成功";
} else {
    echo "Error: " . $sql . "<br>" . $conn->error;
}

// 关闭数据库连接
$conn->close();
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "chat_app";

// 创建数据库连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

$userId1 = 1; // 第一个用户的ID
$userId2 = 2; // 第二个用户的ID

$sql = "SELECT * FROM chat_messages WHERE (sender_id = $userId1 AND receiver_id = $userId2) OR (sender_id = $userId2 AND receiver_id = $userId1) ORDER BY created_at ASC";

$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "发送者: " . $row["sender_id"]. " - 接收者: " . $row["receiver_id"]. " - 消息: " . $row["message"]. "<br>";
    }
} else {
    echo "没有聊天记录.";
}

// 关闭数据库连接
$conn->close();
?>