我想要做的就是INSERT在我的數(shù)據(jù)庫的用戶，但IF EXISTS它應該UPDATE排，ELSE INSERT INTO一個新行。Ofcourse我連接到數(shù)據(jù)庫第一和GET的$name，$email并$birthday從URL字符串。$con=mysqli_connect("localhost","---","---","---");// Check connectionif (mysqli_connect_errno())  {  echo "Failed to connect to MySQL: " . mysqli_connect_error();  }$name=$_GET['name']; $email=$_GET['email'];$birthday=$_GET['birthday'];可以，但是只添加新行；mysqli_query($con,"INSERT INTO subs (subs_name, subs_email, subs_birthday)VALUES ('$name', '$email', '$birthday')");mysqli_close($con);這是我嘗試過的；mysqli_query($con,"INSERT INTO subs (subs_name, subs_email, subs_birthday)VALUES '$name', '$email', '$birthday'ON DUPLICATE KEY UPDATE subs_name = VALUES($name), subs_birthday = VALUES($birthday)");mysqli_close($con);和mysqli_query($con,"IF EXISTS (SELECT * FROM subs WHERE subs_email='$email')    UPDATE subs SET subs_name='$name', subs_birthday='$birthday' WHERE subs_email='$email'ELSE    INSERT INTO subs (subs_name, subs_email, subs_birthday) VALUES ('$name', '$email', '$birthday')");mysqli_close($con);和mysqli_query($con,"IF NOT EXISTS(SELECT * FROM subs WHERE subs_email='$email')BeginINSERT INTO subs (subs_name, subs_email, subs_birthday)VALUES ('$name', '$email', '$birthday')End");mysqli_close($con);但是它們都不起作用，我在做什么錯？任何幫助是極大的贊賞！