PHP code works on server but throws errors in localhost - php

Question

for($i=0;$cast_row = mysql_fetch_array($res);$i++)
{
$cast['id'][] = $cast_row['user_id'];
$cast['role'][] = $cast_row['role'];
$cast['role_name'][] = $cast_row['role_name'];
$cast['is_approved'][] = $cast_row['is_approved'];
$cast['movie_id'][] = $cast_row['movie_id'];
}
for($i=0;$i<count($cast['id']);$i++) //LINE 31
{
$output .= "<tr>";
$mname = getMovieNameById($m_id);
$output .= "<td><a href='single.php?id=$m_id'>$mname</a></td>";
$aname = getArtistNameById($cast['id'][$i]);
$output .= "<td><a href=project.php?id={$cast['id'][$i]}>$aname</a></td>";
}
This code works fine in the web server but throws errors(notice) when executed on localhost
Notice: Undefined index: id in C:\wamp\www\Tinyflick\managemovie.php on line 31
What can be the problem? The rest of the code seems to work just fine

Answer 1

It kind of a silly mistake..
Its solved. Thanks to nico's comment
The error reporting level in localhost is different from the one on the server.
Changing that will do the trick.
The following code will show the all the errors and warnings
error_reporting(E_ALL)
Warnings are usually disabled on a production server. For more info refer the documentation of the said function

Answer 2

i guess the mysql result is just empty ! :)
try dumping the content of the row you get back.
btw, you could improove your code by doing something like this:
while($row = mysql_fetch_array($res)) { // iterates as long there is content
//do something with the $row... like your second for block! ;)
}

Answer 3

it turns out that $cast array is empty as you are not properly fetching the data from database.
if the error reporting is turned off in your server then you will not see any errors.
instead of for loop use the while loop, to iterate through the data fetched from database.
$cast = array();
while($row = mysql_fetch_array($res)) {
$cast['id'][] = $row['user_id'];
$cast['role'][] = $row['role'];
$cast['role_name'][] = $row['role_name'];
$cast['is_approved'][] = $row['is_approved'];
$cast['movie_id'][] = $row['movie_id'];
}
and then you can run the for loop.

Answer 4

I guess that if you want supress those notices, add the following line before the loop:
$cast = array('id'=>array(), 'role'=>array(), 'role_name'=>array(), 'is_approved'=>array(), 'movie_id'=>array() );
to initialize the variable.