MySQL PHP：检查行是否存在

这应该可以解决问题：将结果限制为1行；如果返回一行，

$lectureName

function checkLectureStatus($lectureName){    $con = connectvar();    mysql_select_db("mydatabase", $con);    $result = mysql_query(        "SELECT * FROM preditors_assigned WHERe lecture_name='$lectureName' LIMIT 1");    if(mysql_fetch_array($result) !== false)        return 'Assigned';    return 'Available';}