Question

I’m getting the following message:

Notice: Undefined variable: dbh in /var/www/PDO/Functions/PDOFunctions.php on line 12 Fatal error: Call to a member function prepare() on a non-object in /var/www/PDO/Functions/PDOFunctions.php on line 12

$dbh = new PDO('mysql:host=localhost;dbname=pdo', 'root', 'xxxxxxxxxxx');
global  $dbh;


function PDOFetch($Var)
{
    $sth = $dbh->prepare("$Var"); //Error Line
    $sth->execute();
    $result = $sth->fetchAll();
    return $result; 
}

function PDONumb ($Var)
{
    $Query = $dbh->prepare("{$Var}");
    $Execute->execute();
    $count = $Execute->rowCount();
    return $count;
}

What is the problem with my code?

Answer 1

In PHP, to access a global variable in a function, you have to declare that it belongs to global scope by using the global keyword.

function PDOFetch($Var)
{
    global $dbh;
    $sth = $dbh->prepare("$Var"); //Error Line
    $sth->execute();
    $result = $sth->fetchAll();
    return $result; 
}

All variables used in a function are local to that function unless declared to be imported from the global scope.

The NOTICE error is a helpful warning that you may be doing something you didn’t expect.