Question

I have the following code:

function user_name($id) {
    $eqpt_name1 = $this->sql->query("SELECT `f_val` FROM `profiles` WHERE `u_id` = $id AND `f_id` = 1");
    $eqpt_name1_2 = $eqpt_name1->fetch();
    $name1 = $eqpt_name1_2['f_val'];

    $eqpt_name2 = $this->sql->query("SELECT `f_val` FROM `profiles` WHERE `u_id` = $id AND `f_id` = 2");
    $eqpt_name2_2 = $eqpt_name2->fetch();
    $name2 = $eqpt_name2_2['f_val'];

    $name3 = $name1 . " " . $name2;

    return $name3;
}

what it does is take the provided user id ($id) and gets the First ($name1) and Last ($name2) name of the user and then outputs it.

I call it by doing the following

$username = user_name($_SESSION['user_id']);

$_SESSION['user_id'] is 1, for example.

When I manually put the code in a PHP file, it works fine. But when I use a function so I can use it globally over the entire site so I don’t have to have that long query code on every page, Apache gives me this error:

PHP Fatal error: Call to a member function query() on a non-object

I’ve never written a function that has a query in it before and not sure what I am doing wrong.

Answer 1

Judging by how you’re calling it, that’s just a global function; $this won’t be defined, and so you can’t use $this->sql. If you have a global variable called $sql, tell PHP that you’re using it:

function user_name($id) {
    global $sql;

    $eqpt_name1 = $sql->query("SELECT `f_val` FROM `profiles` WHERE `u_id` = $id AND `f_id` = 1");
    $eqpt_name1_2 = $eqpt_name1->fetch();
    $name1 = $eqpt_name1_2['f_val'];

    $eqpt_name2 = $sql->query("SELECT `f_val` FROM `profiles` WHERE `u_id` = $id AND `f_id` = 2");
    $eqpt_name2_2 = $eqpt_name2->fetch();
    $name2 = $eqpt_name2_2['f_val'];

    $name3 = $name1 . " " . $name2;

    return $name3;
}

Also, you’re using PDO, so why aren’t you using prepared statements? And you can simplify things a little further, too:

function user_name($id) {
    global $sql;

    $query = $sql->prepare('SELECT `f_val` FROM `profiles` WHERE `u_id` = :id AND `f_id` IN (1, 2) ORDER BY `f_id`;');
    $query->execute(array(':id' => $id));

    return implode(' ', $query->fetchAll(PDO::FETCH_COLUMN));
}