Question

I am having trouble being able to insert QuestionId into the Answer Table.

The Question inserts with no problem, but I am trying to retrieve the QuestionId from the Question Table which is an auto increment into the Answer Table by finding the SessionId and QuestionNo that particular QuestionId belongs to. Instead it keeps displaying 0 for QuestionId when inserted into Answer Table.

Now I know the query which tries to perform the select for each QuestionId from the Question Table is correct as this has been tested. I think the problem is where I have placed my code but I am not sure?

Here are the db tables:

Question Table

QuestionId (auto)  SessionId  QuestionNo
4                  2          1
5                  2          2
6                  2          3

Answer Table at moment:

AnswerId (auto)  QuestionId  Answer
7                0           A
8                0           C
9                0           A
10               0           B
11               0           True

What Answer Table should look like:

AnswerId (auto)  QuestionId  Answer
7                4           A
8                4           C
9                5           A
10               5           B
11               6           True

Below is the code:

 $questionsql = "INSERT INTO Question (SessionId, QuestionNo) 
    VALUES (?, ?)";
if (!$insert = $mysqli->prepare($questionsql)) {
    // Handle errors with prepare operation here
    echo __LINE__.': '.$mysqli->error;
}

 $answersql = "INSERT INTO Answer (QuestionId, Answer) 
    VALUES (?, ?)";
if (!$insertanswer = $mysqli->prepare($answersql)) {
    // Handle errors with prepare operation here
    echo __LINE__.': '.$mysqli->error;
}



//make sure both prepared statements succeeded before proceeding
if( $insert && $insertanswer)
{
    $sessid =  $_SESSION['id'] . ($_SESSION['initial_count'] > 1 ? $_SESSION['sessionCount'] : '');
    $c = count($_POST['numQuestion']);

    for($i = 0;  $i < $c; $i++ )
    {


            $insert->bind_param("ii", $sessionid, $_POST['numQuestion'][$i]);

            $insert->execute();

            if ($insert->errno) 
            {
                // Handle query error here
                echo __LINE__.': '.$insert->error;
                break 1;
            }
}

        $results = $_POST['value'];
        foreach($results as $id => $value) 
        {
            $answer = $value;

            $lastID = $id;

            $questionidquery = "SELECT QuestionId FROM Question WHERE (QuestionNo = ? AND SessionId = ?)";

        if (!$questionidstmt = $mysqli->prepare($questionidquery)) {
        // Handle errors with prepare operation here
          echo __LINE__.': '.$mysqli->error;
        }


        // Bind parameter for statement
        $questionidstmt->bind_param("ii", $lastID, $sessionId);

        // Execute the statement
        $questionidstmt->execute();

                    if ($questionidstmt->errno) 
                    {
                        // Handle query error here
                        echo __LINE__.': '.$questionidstmt->error;
                        break 2;
                    }

        // This is what matters. With MySQLi you have to bind result fields to
        // variables before calling fetch()
        $questionidstmt->bind_result($quesid);

        // This populates $optionid
        $questionidstmt->fetch(); 

        $questionidstmt->close(); 



            foreach($value as $answer) 
            {
                $insertanswer->bind_param("is", $quesid, $answer);

                $insertanswer->execute();

                if ($insertanswer->errno) {
                    // Handle query error here
                    echo __LINE__.': '.$insertanswer->error;
                    break 3;
                }
            }
        }


    //close your statements at the end


    $insertanswer->close();
    $insert->close();
}

?>

UPDATE:

Results from var_dump($_POST);

array(8) { 
["numberAnswer"]=> array(2) { 
         [0]=> string(1) "1" 
         [1]=> string(1) "1" 
         } 
         ["numQuestion"]=> array(2) 
         { 
         [0]=> string(1) "1" 
         [1]=> string(1) "2" 
         } 
         ["questionText"]=> array(2) { 
         [0]=> string(12) "What is 2+2?" 
         [1]=> string(12) "What is 4+4?" 
         } 
         ["gridValues"]=> array(2) { 
         [0]=> string(1) "4" 
         [1]=> string(1) "4" 
         } 
         ["reply"]=> array(2) { 
         [0]=> string(6) "single" 
         [1]=> string(6) "single" 
         } 
         ["textWeight"]=> array(2) { 
         [0]=> string(1) "5" 
         [1]=> string(1) "5" 
         } 
         ["submitDetails"]=> string(14) "Submit Details" ["value"]=> array(2) { 
         [1]=> array(1) { 
         [0]=> string(1) "B" 
         } 
         [2]=> array(1) { 
         [0]=> string(1) "D" 
         } 
         } 
         } 

Answer 1

Right now your QuestionID is coming from $_POST['value'], which is probably not what you want… you need to get the automatically generated QuestionID from mysql after each question is inserted.

You can retrieve the last generated ID using $mysqli->insert_id. Do this after each call to $insert->execute();, then use those IDs when you go to insert your answers.

Edit 1:

You should be using $mysqli->insert_id, because insert_id is only valid on a connection object (yours is called $mysqli).

You also need to assign the insert_id to something. I’m having trouble following your code but I think what you want is to store question IDs in an array for later use, something like this:

$question_ids[$i] = $mysqli->insert_id

I’m at a loss for what you’re trying to do after this, I guess you pull in some answers with a corresponding question number but… perhaps if you can post the output of var_dump($_POST) we will understand a bit better. In any case you will need some kind of a loop that inserts the answers for each question, and you can (hopefully) use the array $question_ids[$i] to retrieve the QuestionIDs.

Edit 2:

Here is some sample code (untested), try to get this working before getting fancy with $_POST and $_SESSION

<?php
$questions = array(
    array(2, 1),
    array(2, 2),
    # etc
);
$answers = array(
    array(A, C),
    array(A, B),
);

$questionsql = "INSERT INTO Question (SessionId, QuestionNo) VALUES (?, ?)";  
if (!$insert = $mysqli->prepare($questionsql)) {
    die('couldn\'t prepare statement 1');
}

$answersql = "INSERT INTO Answer (QuestionId, Answer) VALUES (?, ?)";
if (!$insertanswer = $mysqli->prepare($answersql)) {
    die('couldn\'t prepare statement 2');
}

$c = count($questions);

for($i = 0;  $i < $c; $i++)
{
    $insert->bind_param("ii", $questions[$i][0], $questions[$i][1]);
    $insert->execute();

    if ($insert->errno) 
    {
        die("Error inserting question $i");
    }

    $lastID = $mysqli->insert_id;

    foreach ($ans in $answers[$i])
    {
        $insertanswer->bind_param("is", $lastID, $ans);

        $insertanswer->execute();

        if ($insertanswer->errno) {
            die("Error inserting answer to question $i");
        }
    }

}

$insertanswer->close();
$insert->close();
?>