finding the last row

Posted: Thu Jan 11, 2007 9:05 pm

I've been working on a chemistry practice module for a chemistry teacher friend of mine. I've finished the first go round of 9 exercises with 25 questions each and it all works great.

But I'd like to add something, after the student completes the last question ($pqnum = there are no more rows) they get page that they input their name and then submit and then the page outputs their name in the middle of a completion certificate.

In other words,
something like
if there are no more rows
header (Location: "finished.php)

I have the code for the finished form and it works, now I'm trying to find the place for it in the main code. I think it should go in the following function, but not sure, and not sure exactly how.

Any ideas?

Code:

function check($pqnum){


  $query  = "SELECT  pos_sub, neg_sub FROM chem_formulas1 WHERE qnum=$pqnum";


  $qresult = mysql_query($query) or die("Invalid query: $query") ;


  $row = mysql_fetch_array($qresult) or die("You are done... no more questions"); //just for testing gb


  $pos_sub  = $row['pos_sub'];


  $neg_sub  = $row['neg_sub'];


  if (($_POST['pos_try']<>$pos_sub)


  || ($_POST['neg_try']<>$neg_sub)) {


      return FALSE;


    }


    else {


      return TRUE;


    }


}





if (!isset($_POST['qnum'])){


  $pqnum=1;


}


else {


  $pqnum=$_POST['qnum'];


}





if (isset($_POST['submit'])){


 if (check($pqnum)){


 echo "$randimg Good Work!";


  $pqnum++;


} else {


  echo "<img src=\"images/question.gif\" alt=\"Try Again!\" title=\"Try Again!\"></img> Wrong... try again";


}}





show_form($pqnum);

Regular Joined: Mar 14, 2005 Posts: 91

Maybe you can use this

Code:




$query = "SELECT MAX(qnum) as last_question FROM chem_formulas1";


$result = mysql_query($query);


$row = mysql_fetch_array($result);





$last_question = $row['last_question'];

Posted: Mon Jan 15, 2007 8:38 am

I've finished the project.
And solved the above problem with this snippet from the function that displays the question form.

Code:










function show_form($pqnum){


  $query  = "SELECT qnum, reactant, pos, pos_sub, neg, neg_sub FROM chem_formulas1 WHERE qnum=$pqnum";


  $qresult = mysql_query($query) or die("Invalid query: $query") ;


//was:


//  $row = mysql_fetch_array($qresult) or die("  You are done... no more questions. ");


//changed to


    $row = mysql_fetch_array($qresult) or header("Location: finished1.php");