从数据库中提取包含多个答案的调查

Question

I have a working survey that pulls each question and any related answers from multiple tables. Each question is stored in the following table:

• tblQuestions, with the fields:
• qID
• qText.

The related answers are stored in the table:

• tblPossAnswers, with the fields:
• aID
• qID
• answerText.

So, I would have 3 possible answers for each question. My sql to pull everything is:

select * from tblQuestions, tblPossAnswers where
tblPossAnswers.qID = tblQuestions.qID
order by tblQuestions.qID ASC

And my PHP to display it:

while ($row = mysql_fetch_array($result)) {

echo "<p>" . $row['qText'] . "</p><br />";
echo "<input type='radio' name='".$row['qID']."' value='".$row['aID']."' />";
echo $row['answerText'];
}

The problem is this is displaying the qText every time it displays a possible answer. So it looks like:

• Question 1
• Possible answer 1
• Question 1
• Possible answer 2
• Question 1
• Possible answer 3
  
  
• Question 2
• Possible answer 1
• Question 2
• Possible answer 2
• Question 2
• Possible answer 3

What I would like to do is have the qText only display when the first possible answer is pulled. I'm still somewhat of a newb to MySQL, so the solution might be something very simple that I'm just not seeing.

Answer 1

You can either test for whether the question has changed within your PHP loop:

while ($row = mysql_fetch_array($result)) {
  if ($row['qID'] != $lastQuestionID) {
    echo "<p>" . $row['qText'] . "</p><br />";
    $lastQuestionID = $row['qID'];
  }
  echo "<input type='radio' name='".$row['qID']."' value='".$row['aID']."' />";
  echo $row['answerText'];
}

Or else you can group the MySQL results by question using GROUP_CONCAT, specifying a separator on which you then split the answers in PHP:

select *, group_concat(answerText separator char(30)) as answers
from tblQuestions join tblPossAnswers using (qID)
group by tblQuestions.qID
order by tblQuestions.qID ASC

Then:

while ($row = mysql_fetch_array($result)) {
  echo "<p>" . $row['qText'] . "</p><br />";
  foreach (explode(chr(30), $row['answers']) as $answer) {
    echo "<input type='radio' name='".$row['qID']."' value='".$answer."' />";
    echo $answer;
  }
}