PHP/MySQL Quiz - retrieving random records

[paulobetto]

Hi everybody,

I have downloaded an old PHP/MySQL Quiz code from GetFreeSofts.com and it works well retrieving all records from a table. But when I try to retrieve random records (eg. 40 records of 100 records thar are stored in table) the answers aren't correctly.

Can anyone give me a help? Thanks!

Below are the table structure and the code.

CREATE TABLE quiz (
id tinyint(4) NOT NULL auto_increment,
q text NOT NULL,
question text NOT NULL,
opt1 text NOT NULL,
opt2 text NOT NULL,
opt3 text NOT NULL,
answer text NOT NULL,
PRIMARY KEY (id)
) TYPE=MyISAM;

<?php

include("contentdb.php");

$display = mysql_query("SELECT * FROM $table ORDER BY RAND() LIMIT=40",$db);
	
if (!$submit) {


	echo "<form method=post action=$PHP_SELF>";
	echo "<table border=0>";

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

	$id = $row["id"];
	$question = $row["question"];
	$opt1 = $row["opt1"];
	$opt2 = $row["opt2"];
	$opt3 = $row["opt3"];
	$answer = $row["answer"];

	echo "<tr><td colspan=3><br><b>$question</b></td></tr>";
	echo "<tr><td>$opt1 <input type=radio name=q$id value=\"$opt1\"></td><td>$opt2 <input type=radio name=q$id value=\"$opt2\"></td><td>$opt3 <input type=radio name=q$id value=\"$opt3\"></td></tr>";

	}

	echo "</table>";
	echo "<input type='submit' value='See how you did' name='submit'>";
	echo "</form>";

}

elseif ($submit) 

{

	$score = 0;
	$total = mysql_num_rows($display);
		while ($result = mysql_fetch_array($display)) 
		
		
		{
		
			$answer = $result["answer"];
			$q = $result["q"];
			
		if ($$q == $answer) 
		{
		$score++; 
		}
	
	}
	
	echo "<p align=center><b>You scored $score out of $total</b></p>";
	echo "<p>";
	
	if   ($score == $total) {
	echo "Congratulations! You got every question right!";
	}
	elseif ($score/$total < 0.34) {
	echo "Oh dear. Not the best score, but don't worry, it's only a quiz.";
	}
	elseif ($score/$total > 0.67) {
	echo "Well done! You certainly know your stuff.";
	}
	else {
	echo "Not bad - but there were a few that caught you out!";
	}

echo "</p>";

echo "<p>Here are the answers:";

echo "<table border=0>";
$display = mysql_query("SELECT * FROM $table ORDER BY RAND() LIMIT=40",$db);
while ($row = mysql_fetch_array($display)) {

$question = $row["question"];
$answer = $row["answer"];
$q = $row["q"];

echo "<tr><td><br>$question</td></tr>";

if ($$q == $answer) 
		{
		echo "<tr><td>&raquo;you answered ${$q}, which is correct</td></tr>";
		}
elseif ($$q == "") {
echo "<tr><td>&raquo;you didn't select an answer. The answer is $answer</td></tr>";
}
else {
echo "<tr><td>&raquo;you answered ${$q}. The answer is $answer</td></tr>";
}

}
echo "</table></p>";



}

?>