调用成员函数非对象

Question

I'm beginning with PHP and i need your help.

I create a try to list all members who has the same interest that the current_member( i mean the connected member ).

I write this :

$current_members = params('current_member');
    $members_all = option('db')->query('SELECT * FROM members WHERE interest = $current_members["interest"] ORDER BY lastname, firstname')->fetchAll();

    set('members_all', $members_all);

When I go on my page I have the error : Fatal error: Call to a member function fetchAll() on a non-object

And in my view I just write this :

        <h2 id="member-<?= $member['id'] ?>">

            <?= avatar_tag($member,'30x30') ?>

            <a href="<?=member_url_for($member)?>"><?=$member['firstname']?><small> <?= $member['lastname'] ?></small></a>

        </h2>

I dont understand this error, anyone can help me ?

Thank's for your help.

Answer 1

Do not chain calls to query() and fetchAll() like you are doing. That's bad practice. Never assume your query worked, always check to see if it did.

$db = option('db');
$query = $db->query('SELECT ...');
if($query === FALSE){
    print_r($db->errorInfo());
    die;
}
$members_all = $query->fetchAll();

_{(Since you are calling fetchAll(), I assume you are using PDO (and not MySQLi))}

Also, do not try to concatenate variables into your SQL query. (P.S. You're not even doing that, you are using single quotes, so $current_members["interest"] is not being read as a variable) That's just asking for an SQL injection attack. What you want to do is use prepared statements.

$db = option('db');
$query = $db->prepare('SELECT * FROM members WHERE interest = ? ORDER BY lastname, firstname');
$exec = $query->execute(array($current_members['interest']));
if($exec === FALSE){
    print_r($query->errorInfo());
    die;
}
$members_all = $query->fetchAll();