// 获取当前用户 UID
$uid = $user['uid']; // 假设 $user 是当前用户信息的变量

// 获取当前时间戳
$currentTimestamp = time();


// 计算30天前的时间戳
$thirtyDaysAgoTimestamp = $currentTimestamp - (30 * 24 * 60 * 60);

// 查询当前用户最近30天的发帖数
$postCount = db_count('thread',array('uid' => $uid, 'create_date'=>array('>'=>$thirtyDaysAgoTimestamp)));