如何在MySQL查询中接受两个正确答案？

Question

我有四个选择，其中两个都是正确答案。

if($isCorrect == "answer1"){
    $sql2 = mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', '1')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer2', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer3', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer4', '0')")or die(mysql_error());
    $msg = 'You questions has been succesfully added!';
  header('location: addQuestions.php?msg='.$msg.'');
exit();
}
if($isCorrect == "answer2"){
    $sql2 = mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer2', '1')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer3', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer4', '0')")or die(mysql_error());
    $msg = 'You questions has been succesfully added!';
  header('location: addQuestions.php?msg='.$msg.'');
exit();
}
if($isCorrect == "answer3"){
    $sql2 = mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer3', '1')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer2', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer4', '0')")or die(mysql_error());
    $msg = 'You questions has been succesfully added!';
  header('location: addQuestions.php?msg='.$msg.'');
exit();
}
if($isCorrect == "answer4"){
    $sql2 = mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer4', '1')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer2', '0')")or die(mysql_error());
    mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer3', '0')")or die(mysql_error());
    $msg = 'You questions has been succesfully added!';
  header('location: addQuestions.php?msg='.$msg.'');
exit();
    }
}

当我运行这些时，只有一个被接受为正确答案。

我的数据库有没有办法接受两个正确答案？我正在使用枚举（0,1）检查正确答案。

Answer 1

稍后可能会有人给出更好的回答，这只是为了让事情顺利进行。

我将首先重构您目前拥有的内容，如下所示：

// note: there are a lot of ways to make the following cleaner (use an array, 
//   write a function, etc.), but for the sake of time and simplicity I'll
//   leave it at this 

// if $isCorrect == "answer1", $answer1Correct = '1', else $answer1Correct = '0'
$answer1Correct = ($isCorrect == "answer1" ? '1' : '0');
$answer2Correct = ($isCorrect == "answer2" ? '1' : '0');
$answer3Correct = ($isCorrect == "answer3" ? '1' : '0');
$answer4Correct = ($isCorrect == "answer4" ? '1' : '0');

mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', $answer1Correct)")or die(mysql_error());
mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer2', $answer2Correct)")or die(mysql_error());
mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer3', $answer3Correct)")or die(mysql_error());
mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer4', $answer4Correct)")or die(mysql_error());
$msg = 'You questions has been succesfully added!';
header('location: addQuestions.php?msg='.$msg.'');
exit();

我不知道你在用sql2做什么，我在这里忽略了它。

到目前为止，这应该与您当前拥有的功能相同

然后，为了进行您想要的更改，我将把$isCorrect从字符串更改为字符串数组。

例如，假设答案1和4都正确：$isCorrect=array（'answer1'，'answer4'）；

然后使用in\u array（），使$answer1Correct部分变为：

// if "answer1" is in the $isCorrect array, set $answer1Correct to '1', otherwise set it to '0'
$answer1Correct = (in_array("answer1", $isCorrect) ? '1' : '0');
$answer2Correct = (in_array("answer2", $isCorrect) ? '1' : '0');
$answer3Correct = (in_array("answer3", $isCorrect) ? '1' : '0');
$answer4Correct = (in_array("answer4", $isCorrect) ? '1' : '0');

编辑：更多改进

您可以将布尔值转换为整数，然后将其转换为字符串，而不是使用三元运算符（condition？true\u value:false\u value）。

（int）true返回整数1，而（string）（int）true返回字符串“1”。

所以你的$答案1正确部分就变成了：$答案1正确=（string）（int）in_array（"答案1"，$is正确）；$答案2正确=（string）（int）in_array（"答案2"，$is正确）；$答案3正确=（string）（int）in_array（"答案3"，$is正确）；$答案4正确=（string）（int）in_array（"答案4"，$is正确）；

但所有这些都有点繁琐，要复制粘贴这么多，一个更简单的选择是用一个函数替换$answer1Correct：

function answerIsCorrect($answerNumber, $allCorrectAnswers) {
  return (string)(int)in_array("answer" . $answerNumber, $allCorrectAnswers);
}

然后您的查询变成：

mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', '$answer1', answerIsCorrect(1, $isCorrect)")or die(mysql_error());

现在您可以将整个事情作为循环进行，因此您的整个脚本可以缩短为：

function answerIsCorrect($answerNumber, $allCorrectAnswers) {
  return (string)(int)in_array("answer" . $answerNumber, $allCorrectAnswers);
} 

$answers = array(
  1 => $answer1,
  2 => $answer2,
  3 => $answer3,
  4 => $answer4
)

for($i = 1; $i <= 4; $i++) {
  mysql_query("INSERT INTO answers (question_id, answer, correct) VALUES ('$lastId', $answers[$i], answerIsCorrect($i, $isCorrect)")or die(mysql_error());
}

如果将$isCorrect从字符串更改为字符串数组，如上所述。