mysql_fetch_assoc() [ SOMEONE HELP! :(( pls.

Im having a problem coding for our project . here's the code

<?php
$value = $_POST['p'];
$host="localhost"; 
$username="root"; 
$password="";
$db_name="dbquiz";


mysql_connect("$host", "$username", "$password")or die("cannot connect"); 
mysql_select_db("$db_name")or die("cannot select DB");


$value = stripslashes($value);
$value = mysql_real_escape_string($value);


$sql='SELECT * FROM `'. $value .'` ORDER BY RAND() LIMIT 100';
$result=mysql_query($sql) or die(mysql_error());


if(result){
while($row = mysql_fetch_assoc($result)) 
    { 
    $q = $row['question']; 
    $c1= "" .$row['choice1']; 
    $c2 ="" .$row['choice2']; 
    $c3 ="" .$row['choice3']; 
    $c4 ="" .$row['choice4']; 
    $a ="".$row['answer'];
    $questions[] = array($q,$c1,$c2,$c3,$c4,$a);
    } 
}
include_once("makequiz.php");


?>

Code (markup):

AND FOR THE makequiz

<?php 
if (isset($_POST['sent'])) {
    for ($i=0;$i<count($questions);$i++) {
        echo($questions[$i][0]." - ");
        if ($_POST['q'.$i]=="c") {
            echo("<b>Correct!</b><br>\n");
            $score++;
        } else {
            echo("<b>Wrong!</b><br>\n");
        }
    }
    $percent = number_format(($score/count($questions))*100,2,".",",");
    echo("<br>".$score." out of ".count($questions)." (".$percent."% right)<br>\n");
} else {
    echo("<form action=\"#\" method=\"post\">\n");
    echo("<input type=\"hidden\" name=\"sent\">\n");
    for ($i=0;$i<count($questions);$i++) {
        echo("<b>".$questions[$i][0]."</b><br><br>\n");
        if ($questions[$i][5]==1) {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"c\"> ".$questions[$i][1]."<br>\n");
        } else {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"w\"> ".$questions[$i][1]."<br>\n");
        }
        if ($questions[$i][5]==2) {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"c\"> ".$questions[$i][2]."<br>\n");
        } else {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"w\"> ".$questions[$i][2]."<br>\n");
        }
        if ($questions[$i][5]==3) {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"c\"> ".$questions[$i][3]."<br>\n");
        } else {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"w\"> ".$questions[$i][3]."<br>\n");
        }
        if ($questions[$i][5]==4) {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"c\"> ".$questions[$i][4]."<br><br>\n");
        } else {
            echo("<input type=\"radio\" name=\"q".$i."\" value=\"w\"> ".$questions[$i][4]."<br><br>\n");
        }
    }
    echo("<input type=\"submit\" value=\"Am I Right?!\">");
} ?>

Code (markup):

When you run the first code.. it's working but when i clicked the submit button this error keeps on showing and i dont know why.. "Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in " can someone help me fix this problem pls? thx in advance.

 

I'm guessing, but use Firefox, add the Firebug and FirePHP addons and change your code to

$sql='SELECT * FROM `'. $value .'` ORDER BY RAND() LIMIT 100'; $result=mysql_query($sql) or die(mysql_error()); 
if(!false === $result) {   fb::log($result);
} else {
  fb::log('Query failed.');
} 
if(result){ while($row = mysql_fetch_assoc($result)) 

Code (markup):

If the query fails, change the code at the top to

$value = $_POST['p'];
fb::log('"'.$value.'"');
...
$value = stripslashes($value); $value = mysql_real_escape_string($value);

fb::log('"'.$value.'"');

Code (markup):

to see what's happening. I suspect that you're getting a blank for $value, so your SQL query is
'SELECT * FROM `` ORDER BY RAND() LIMIT 100';

That will fail, making $result null, making mysql_fetch_assoc($result) fail.

 

It says..

Fatal error: Class 'fb' not found in

hmm.. how can i make the $value not null?

 

Value is what's in $_POST['p'] when you submit. Make sure the page doesn't submit to your PHP file if the element whose ID is p is blank.

"Class 'fb' not found" is due to the fact that you didn't add

    ob_start();
    require('FirePHPCore/fb.php');
    FB::setEnabled(true);

Code (markup):

at the top of your code. It's in the information on the FirePHP site. Once you learn to use FirePHP, you won't write PHP code without it. (ob_start() is required to prevent a "headers already sent" error.)

 

for in the future:

if(result)

Code (markup):

should be if($result)
however, you don't need the if statement, because that's exactly what the while statement is doing.

mysql_connect("$host", "$username", "$password")or die("cannot connect"); 
mysql_select_db("$db_name")or die("cannot select DB");

Code (markup):

should be

mysql_connect($host, $username, $password)or die("cannot connect"); 
mysql_select_db($db_name)or die("cannot select DB");

Code (markup):

it's just a waste of effort and processing time to put the variables in their own double quotes

$value = stripslashes($value);
$value = mysql_real_escape_string($value);

Code (markup):

should be

if(get_magic_quotes_gpc())
{
   $value = stripslashes($value);
}

$value = mysql_real_escape_string($value);

Code (markup):

that way, if you transfer your code to a server that doesn't have magic quotes enabled, it wont screw up your content

$result=mysql_query($sql) or die(mysql_error());

Code (markup):

might want to look at that, i've never done it that way before.

and "makequiz.php" shouldn't effect a function called way up at the top.

as for the error, i'm not sure whats going on, but you could try mysql_fetch_array instead.
oh and you might also want to consider changing LIMIT 100 to LIMIT 0,100
if your using an old version of mysql, it could bug out on that.

 

i dont get it.. ' im noob at this.