我有一个使用mysqli和php制作的applet，人们必须回答来自数据库表的问题。我在一个数据库中有两个表。一个用于问题和答案，而另一个用于记录用户在表单中输入的内容（用户ID由auto_increment生成，一旦有人点击＆＃34;开始测验＆＃34;）。
我的一切工作都很完美，但唯一的问题是，一旦用户回答问题，第一个表（有一个名为＆＃34的列;解决了＆＃34; tinyint（1），从0变为1取决于该人是否解决了这个问题）为所有用户更新其已解决的列。
我想这样做只是为了更新某个id，但我不知道如何。这是我的php的以下代码。
<?php require("../require/exponents_database_connection.php"); ?>
<center><div style="overflow:hidden; border:solid; border-color:#39AEB9; display:inline-block; width: 500px; height:auto;">
<div style="vertical-align: middle; padding:25px;">
<?php
// 3. Use returned data
$exponents = "SELECT * FROM q_exponents WHERE solved = 0 ORDER BY id ASC LIMIT 1 ";
$result_exponents = mysqli_query($connection, $exponents);
$question = mysqli_fetch_assoc($result_exponents);
$getinfo = "SELECT * FROM q_exponents";
$result_getinfo = mysqli_query($connection, $getinfo);
$totsolved = "SELECT * FROM q_exponents WHERE solved=1";
$result_totsolved = mysqli_query($connection, $totsolved);
$totalsolved=mysqli_num_rows($result_totsolved);
$totalquestions=mysqli_num_rows($result_getinfo);
?>
<?php if(!isset($_POST['Submit']) || isset($_POST['Reset'])) { ?>
<div style="display: inline-block;">
<p><b> <?php echo "<p style='font-family:sans-serif;'>".$question["question"]."</p>"; ?> </b></p>
<?php $question_id = (int) $question['id']; ?>
<div style="float:left;">
<form action="" method="post">
<div>
<input type="radio" name="response" value="<?php echo $question["a1"]?>" checked><?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["a1"]."</p>"?>
<input type="radio" name="response" value="<?php echo $question["a2"]?>" style="margin-left:50px;" ><?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["a2"]."</p>"?>
<input type="radio" name="response" value="<?php echo $question["a3"]?>" style="margin-left:50px;" ><?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["a3"]."</p>"?>
<input type="radio" name="response" value="<?php echo $question["a4"]?>" style="margin-left:50px;" ><?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["a4"]."</p>"?>
<input type="hidden" name="question_id" value="<?php echo $question["id"] ?>" />
</div>
</div>
<div class="empty_block"> </div> <br/>
<br><input type="Submit" name="Submit" value="Submit" style="width:150px; height: auto;">
<div class="empty_block"> </div>
</form>
</div>
<?php } elseif(isset($_POST['Submit'])) { ?>
<?php
$previous_question_id = (int) $_POST['question_id']; //calls for previous id before randomising
$exponents = "SELECT * FROM q_exponents WHERE id = $previous_question_id";
$result_exponents=mysqli_query($connection, $exponents);
$question=mysqli_fetch_array($result_exponents); //fetches database randomised data where id = previous id
$response=$_POST['response'];
$a = "a".$previous_question_id;
$current_id=mysqli_query($connection, "SELECT AUTO_INCREMENT FROM information_schema.tables WHERE TABLE_SCHEMA = 'exponents' AND TABLE_NAME = 'a_exponents'")->fetch_object()->AUTO_INCREMENT;
$answers="UPDATE a_exponents SET $a = $response WHERE id = $current_id - 1";
$record_answer=mysqli_query($connection, $answers);
$check_answer = "SELECT * FROM a_exponents";
$result_check_answer = mysqli_query($connection, $check_answer);
$score_result = mysqli_fetch_assoc($result_check_answer);
$totsolved = "SELECT * FROM q_exponents WHERE solved=1";
$result_totsolved = mysqli_query($connection, $totsolved);
$totalsolved=mysqli_num_rows($result_totsolved); //counts how many we have solved
if($response == $question['correct']){
echo "<p style='font-family:sans-serif; color:#83E046;'><b>CORRECT</b></p>"; ?>
<p><b> <?php echo "<p style='display: inline; font-family:sans-serif;'>".$question["question"]."</p>";?>
<p style='display: inline; font-family:sans-serif;'>, x = </p>
<?php echo "<p style='display: inline; font-family:sans-serif;'>".$question["correct"]."</p>";?></b></p>
<?php
$solved = "UPDATE q_exponents SET solved = 1 WHERE id = $previous_question_id";
mysqli_query($connection, $solved); //updates database so that those with previous id are marked as solved
$totalsolved = $totalsolved + 1;?>
<?php
} else {
$solved = "UPDATE q_exponents SET solved =0 WHERE id=$previous_question_id";
mysqli_query($connection, $solved);
echo "<p style='font-family:sans-serif; color:#E04646;'><b>INCORRECT</b></p>"; ?>
<p style='display: inline; font-family: sans-serif;'>Your response was: </p>
<?php
echo $response;
?>
<p><b> <?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["question"]."</p>";?>
<p style='display: inline; font-family:sans-serif;'>, x = </p>
<?php echo "<p style='display:inline; font-family:sans-serif;'>".$question["correct"]."</p>"; ?></b></p>
<?php }?>
<?php if($totalsolved==$totalquestions){?>
<br><form action="" method="post"><input type="submit" name="" value="One More Time" onclick="<?php $solved = "UPDATE q_exponents SET solved = 0"; mysqli_query($connection,$solved);?>"></form>
<?php } elseif ($response !== $question['correct']) { ?>
<br><form action="" method="get"><input type="submit" name="next" value="Try Again"/></form>
<?php } else { ?>
<br><form action="" method="get"><input type="submit" name="next" value="Next Question"/></form>
<?php }
} ?>
</div>
</div></center>
<?php
// 4. Release returned data
mysqli_free_result($result_exponents);
?>
<?php
require("../require/close_connection.php");
?>
<?php
// 2. Perform database query
//collects data from database by a resource
// Test if there was a query error
if (!$result_exponents) {
die("Database query failed.");
}
?>
这些是我的表格： 1.问题表（q_exponents）
+----+-----------------------------------------------------------------------------------+-----+----+-----+-----------+---------+--------+
| id | question | a1 | a2 | a3 | a4 | correct | solved |
+----+-----------------------------------------------------------------------------------+-----+----+-----+-----------+---------+--------+
| 1 | 2<sup>4</sup> × 2<sup>3</sup> = 2<sup>x</sup> | 7 | 4 | 12 | 10 | 7 | 1 |
| 2 | 2<sup>6</sup> × 2<sup>x</sup> = 2<sup>8</sup> | 5 | 2 | 1.5 | 3 | 2 | 1 |
| 3 | <sup>2<sup>12</sup></sup> ⁄ <sub>2<sup>4</sup></sub> = 2<sup>x</sup> | 15 | 5 | 8 | 6 | 8 | 1 |
| 4 | <sup>2<sup>x</sup></sup> ⁄ <sub>2<sup>5</sup></sub> = 2<sup>3</sup> | 3 | 48 | 7 | 8 | 8 | 1 |
| 5 | 2<sup>x</sup> × 2<sup>2</sup> = 2<sup>5</sup> | 3 | 1 | 2.5 | 10 | 3 | 1 |
| 6 | 5<sup>x</sup> × 5<sup>7</sup> = 5<sup>25</sup> | 1 | 32 | 18 | 175 | 18 | 1 |
| 7 | <sup>103<sup>14</sup></sup> ⁄ <sub>103<sup>15</sup></sub> = 103<sup>x</sup> | -1 | 29 | 1 | No Answer | -1 | 0 |
| 8 | <sup>35<sup>17</sup></sup> ⁄ <sub>35<sup>x</sup></sub> = 35<sup>34</sup> | 41 | 2 | 0.5 | -17 | -17 | 0 |
| 9 | 103<sup>x</sup> × 103<sup>-1</sup> = 103<sup>89</sup> | 88 | 89 | 90 | 91 | 90 | 0 |
| 10 | 65<sup>-x</sup> × 65<sup>1</sup> = 65<sup>9</sup> | -10 | 10 | 8 | -8 | -8 | 0 |
| 11 | <sup>3<sup>3x</sup></sup> ⁄ <sub>3<sup>2x</sup></sub> = 3<sup>4</sup> | 2 | 3 | 4 | 5 | 4 | 0 |
| 12 | 4<sup>3x</sup> × 4<sup>2x</sup> = 4<sup>20</sup> | 2 | 3 | 4 | 5 | 4 | 0 |
+----+-----------------------------------------------------------------------------------+-----+----+-----+-----------+---------+--------+
答案 0 :(得分：0)
您为答案表提供的链接已损坏。
你有用户表吗？您必须有一个。无法看到你的答案表是什么样的，我只能建议它看起来像这样：
+--------+-------------+----------------------------+
|user_id | question_id | answer |
+--------+-------------+----------------------------+
| 1 | 1 | their answer |
| 1 | 2 | their next answer |
+--------+-------------+----------------------------+
您还需要使用会话处理（跟踪用户在逐个问题时的跟踪情况，但这不在此范围内。