mysql 签到表结构

CREATE TABLE `user_sign_in` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `user_id` INT NOT NULL,
  `sign_date` DATE NOT NULL,
  `sign_time` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  `status` ENUM('signed', 'unsigned') DEFAULT 'unsigned',
  UNIQUE KEY `unique_user_date` (`user_id`, `sign_date`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

<?php
$userId = 123;
$signDate = date('Y-m-d');

// 检查是否已签到
$sql = "SELECT status FROM user_sign_in WHERE user_id = ? AND sign_date = ?";
$stmt = $pdo->prepare($sql);
$stmt->execute([$userId, $signDate]);
$result = $stmt->fetch();

if ($result['status'] == 'unsigned') {
    // 插入签到记录
    $sql = "INSERT INTO user_sign_in (user_id, sign_date, status) VALUES (?, ?, 'signed')";
    $stmt = $pdo->prepare($sql);
    $stmt->execute([$userId, $signDate]);
    echo "签到成功！";
} else {
    echo "今天已经签到过了！";
}
?>