MySQL Fetch Array Boolean error

Question

This is my code

<?php 
    $result = mysql_query("SELECT * FROM post WHERE username = ".$username." ORDER BY ID DESC ");
    while($row = mysql_fetch_array($result)){ 
    ?>
        <div class="post">
            <a href="/p/<?php echo $row['ID']; ?>" class="post-title"><?php echo $row['title']; ?> - (Rating: <?php echo $row['rank']; ?>)</a>
            <p class="post-content"><?php echo $row['description']; ?><br /><br />On <?php echo $row['date']; ?></p>
        </div>
    <?php }; ?>

But I get this error:

Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in /*/programs/user.php on line 77

It is, when I run a search on PHPMyAdmin and show the PHP code, this is what I get: $sql = "SELECT * FROM `vb_posts` WHERE `username` = \'joshblease\' ORDER BY `ID` DESC"; — Blease, Oct 14 '12 at 14:01
use strip slashes on $username, also run query outside PHP and check if its returning something. — Riz, Oct 14 '12 at 14:03

score 3 · Accepted Answer · edited May 23 '17 at 11:48

3

I suspect that you forgot it to wrap it with single quotes

$result = mysql_query("SELECT * 
                       FROM post 
                       WHERE username = '".$username."' 
                       ORDER BY ID DESC ");

but you are still vulnerable with sql injection. Please take time to read on the article below

Best way to prevent SQL injection in PHP?

edited May 23 '17 at 11:48

Community

1
1

answered Oct 14 '12 at 14:02

John Woo

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somewhat similar on this one [mysql_fetch_array() expects parameter 1 to be resource, boolean given in select](http://stackoverflow.com/questions/2973202/mysql-fetch-array-expects-parameter-1-to-be-resource-boolean-given-in-select) – John Woo Oct 14 '12 at 14:06

score 0 · Answer 2 · answered Oct 14 '12 at 14:02

mysql_query() returns a boolean FALSE if there was an error. So there was an error in your SELECT statement.

You should check if $result === FALSE before trying to do something with $result. If $result === FALSE, use mysql_error() to find out more about what went wrong.

Note that mysql_query() and other mysql_* functions are deprecated. Move to mysqli_* or PDO functions/methods instead. One great feature of PDO and mysqli_* is prepared statements. They will help you avoid SQL injection attacks.

MySQL Fetch Array Boolean error

2 Answers2