Question

我正在为大学作业制作一个基本的民意调查脚本，但我无法更新单行SQL。相反，所有行都是更新。

所以这里我们得到了脚本的第一部分，它从所选的轮询ID中提取所有相关记录。让我们调用这个脚本 show.php

 <?php

     $pid = (int)$_GET['pid'];

     $query = " 
            SELECT 
                 Player_ID,
                 Player_Name
            FROM players WHERE Team_ID = :pid
        "; 

    $query_params = array( 
            ':pid' => $pid, 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $rows = $stmt->fetchAll();

    ?>

    <div class="container contain well">

    <h3>Please select player</h3>

    <form action="vote.php" method="post">
    <input type="hidden" name="pid" value="<?php echo $_GET['pid']; ?>" />
    <?php foreach($rows as $row): ?>
          <input type="radio" name="player" value="<?php echo $row['Player_ID']; ?>" id="<?php echo $row['Player_ID']; ?>"><label for="<?php echo $row['Player_ID']; ?>"><?php echo $row['Player_Name']; ?></label><br>
    <?php endforeach; ?> 
    <input type="submit" value="Vote &raquo;" class="btn btn-primary" />
    </form>

    </div>

现在用户选择他希望投票给哪个玩家的脚本发送一个POST请求让我们说 vote.php

    <?php
         require("database.obj.php");

            $pid = (int)$_POST['pid'];

            $query = " 
                UPDATE players 
                SET 
                    Player_Votes = Player_Votes+1; 
                WHERE
                    ( Player_ID = :player )
            "; 

            $query_params = array( 
                    ':player' => $_POST['player']
            ); 

            try 
            { 
                $stmt = $db->prepare($query); 
                $result = $stmt->execute($query_params); 
            } 
            catch(PDOException $ex) 
            { 
                die("Failed to run query: " . $ex->getMessage()); 
            } 

            header("Location: results.php?pid=$pid");
            die("Redirecting to results.php?pid=$pid");

最后是 results.php 页面，其中显示了结果

     $pid = (int)$_GET['pid'];

     $query = " 
            SELECT 
                 Player_ID,
                 Player_Name,
                 Player_Votes
            FROM players WHERE Team_ID = :pid
        "; 

    $query_params = array( 
            ':pid' => $pid, 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $rows = $stmt->fetchAll();
    ?>

    <div class="container contain well">

    <h3>Player results</h3>

    <?php foreach($rows as $row): ?>
          <p><?php echo $row['Player_Name']; ?>
          <div class="progress">
              <div class="progress-bar" role="progressbar" aria-valuenow="<?php echo $row['Player_Votes']; ?>" aria-valuemin="0" aria-valuemax="100" style="width:<?php echo $row['Player_Votes']; ?>%;">
              <?php echo $row['Player_Votes']; ?> Votes
              </div>
          </div>
    <?php endforeach; ?> 

    </div>

问题在于show.php或vote.php（vote.php处理UPDATE查询）但是我不知道问题出在哪里。正如我所说的那样，数据被插入到Players_Votes中，但它插入了所有与玩家相关的玩家，比如说Team_ID = 1

有人可以帮助我吗？提前谢谢。

Answer 1

在;子句之前的更新语句中有分号（where）。这会将您的语句分成两个语句 - 一个update没有where子句，它会更新所有记录（如您所述），以及一个以where开头的语句它不是有效的SQL。

要解决此问题，您应该删除该分号：

$query = " 
            UPDATE players 
            SET 
                Player_Votes = Player_Votes+1 -- Semicolon removed here
            WHERE
                ( Player_ID = :player )
        ";

PHP PDO更新多个记录而不是一个

1 个答案: