Notice: Undefined offset: 0 in

user_825073 0
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I am getting this PHP error, what does it mean?

Notice: Undefined offset: 0 in 
C:\xampp\htdocs\mywebsite\reddit_vote_tut\src\votes.php on line 41

From this code:

<?php 
include("config.php"); 

function getAllVotes($id) 
{ 
    $votes = array(); 
    $q = "SELECT * FROM entries WHERE id = $id"; 
    $r = mysql_query($q); 
    if(mysql_num_rows($r)==1)//id found in the table 
    { 
        $row = mysql_fetch_assoc($r); 
        $votes[0] = $row['votes_up']; 
        $votes[1] = $row['votes_down']; 
    } 
    return $votes; 
} 

function getEffectiveVotes($id) 
{ 
        $votes = getAllVotes($id); 
        $effectiveVote = $votes[0] - $votes[1];    //ERROR THROWN HERE
        return $effectiveVote; 
} 

$id = $_POST['id']; 
$action = $_POST['action']; 

//get the current votes 
$cur_votes = getAllVotes($id); 

//ok, now update the votes 

if($action=='vote_up') //voting up 
{ 

    $votes_up = $cur_votes[0]+1;     //AND ERROR THROWN HERE


    $q = "UPDATE threads SET votes_up = $votes_up WHERE id = $id"; 
} 
elseif($action=='vote_down')
{ 
    $votes_down = $cur_votes[1]+1; 
    $q = "UPDATE threads SET votes_down = $votes_down WHERE id = $id"; 
} 

$r = mysql_query($q); 
if($r)
{ 
    $effectiveVote = getEffectiveVotes($id); 
    echo $effectiveVote." votes"; 
} 
elseif(!$r) //voting failed 
{ 
    echo "Failed!"; 
} 
?>
html php
15 Answers

I encountered this as well and the solution is simple, dont hardcode the array index position in your code.
Instead of $data[0]['somekey'] do foreach($data as $data_item) { echo $data_item['somekey']; }
If there is an array or more you can perform your desired action inside the loop, but if it's undefined it will not bring an error. you can also add other checks on top of that. You could also add a variable and increment it in a for in loop to limit your looping if you want only the first positions or something.

user_99436480

In my case it was a simple type

$_SESSION['role' == 'ge']

I was missing the correct closing bracket

$_SESSION['role'] == 'ge'
user_7779820

If you are using dompdf/dompdf and error occure in vendor/dompdf/dompdf/src/Cellmap.php then It looks like we're using the wrong frame id in the update_row_group method. Initial testing seems to confirm this. Though that may be because this is strictly a paged table issue and not too many of the documents in my test bed have paged tables.

Can you try changing line 800 to:

$r_rows = $this->_frames[$g_key]["rows"];
($g_key instead of $r_key)

https://github.com/dompdf/dompdf/issues/1295

user_69076450

Use mysql row instead

mysql_fetch_row($r)

Meanwhile consider using mysqli or PDO

?>

user_107714070

Try seeding data with command: php artisan db:seed.

user_165255830
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