PHP/Mysql/Highscore表-如何检查现有分数并替换它们

我有一个简单的游戏和高分系统。用户可以写下他的名字，他的分数将保存在highscore表中。问题是：当一个用户用同一个名字玩几次游戏时，数据库中总是有一个新条目。如何更改代码，使每个名称只有一个条目。我如何检查现有的用户名分数，并且只在更好的时候更新分数？如何在我的代码中实现这一点？提前谢谢

<?php
header('Access-Control-Allow-Origin: *');

require 'config.php';

mysql_connect("$host", "$username", "$password")or die("cannot connect"); 
mysql_select_db("$db_name")or die("cannot select DB");

if(isset($_GET['name']) && isset($_GET['score'])) {

 //Lightly sanitize the GET's to prevent SQL injections and possible XSS attacks
 $name = strip_tags(mysql_real_escape_string($_GET['name']));
 $score = strip_tags(mysql_real_escape_string($_GET['score']));
 $sql = mysql_query("INSERT INTO `$tbl_name` (`id`,`name`,`score`) VALUES ('','$name','$score');");

 if($sql){

      //The query returned true - now do whatever you like here.
      echo 'Your score was saved. Congrats!';

 }else{

      //The query returned false - you might want to put some sort of error reporting here. Even logging the error to a text file is fine.
      echo 'There was a problem saving your score. Please try again later.'.mysql_error();;

 }

}else{
 echo 'Your name or score wasnt passed in the request. Make sure you add ?name=NAME_HERE&score=1337 to the tags.';
}

mysql_close($dblink);//Close off the MySQL connection to save resources.
?>

---

您可以这样尝试：

使您的姓名列唯一：

CREATE TABLE highscore (
    name VARCHAR(255) NOT NULL UNIQUE,
    id INT NOT NULL UNIQUE,
    score INT NOT NULL DEFAULT 0
    PRIMARY KEY (username, id)
);

如果用户存在，则check的分数越高。然后使用新的highscore进行更新

INSERT INTO 
    `$tbl_name`
SET
    `name` = '$name',
    `score` = '$score'
ON DUPLICATE KEY UPDATE
    `score` = IF (VALUES(`score`) > `score`, VALUES(`score`), `score`) ;

这是否检查现有分数，并仅在新分数更好时更新？对不起，我忘记检查分数了。等一下。好的，你现在可以测试了。很好，谢谢。你知道如何将大写的“姓名”写入数据库吗？好极了，你需要通过对方的姓名来告诉对方他们有回复。我认为@hansistr没有收到你的留言，因为他/她把同样的问题重新问了一遍。
 if(isset($_GET['name']) && isset($_GET['score'])) {
    $name = strip_tags(mysql_real_escape_string($_GET['name']));
    $score = strip_tags(mysql_real_escape_string($_GET['score']));

    $checkExist = mysql_query("SELECT `name`, `score` FROM `$tbl_name` WHERE `name` = '$name'");
    $row = mysql_fetch_assoc($checkExist);

    if (mysql_num_rows($checkExist) > 0){
        if ($score > $row['score']){
            $sql = mysql_query("UPDATE `$tbl_name` SET `score` = '$score' WHERE `name` = '$name'");
        } else {
            // ERROR MSG: Your new score is lower.(not updating the database)
        }
    } else {
        $sql = mysql_query("INSERT INTO `$tbl_name` (`id`,`name`,`score`) VALUES ('','$name','$score');");
    }

 if ($sql){
      //The query returned true - now do whatever you like here.
      echo 'Your score was saved. Congrats!';
 } else {    
      //The query returned false - you might want to put some sort of error reporting here. Even logging the error to a text file is fine.
      echo 'There was a problem saving your score. Please try again later.'.mysql_error();;

 }