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POAvoiding use of a global database handler variable in PHP, to someone who is new to OOP?
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copied!<p><strong>EDIT:</strong> This question is <strong>not</strong> a duplicate. Here's why. None of those answers were in the least bit helpful because I completely new to OOP - I need an answer tailored to my level of understanding. Just because the question <strong>appears</strong> to be similar, the asker is not - not to mention I specifically requested an 'understandable' answer in the first place. </p> <hr> <p>I'm still reasonably new to PHP overall, and even newer to Object Oriented PHP, having only just started educating myself on it within the past week, and I am still unable to grasp some concepts such as inheritance and what class abstraction is - some of it I've been able to pick up reasonably quickly as I've been working with PDO to handle my database connections and queries for a while now, but otherwise I'm still a newbie at OOPHP, so bear with me if my question seems a bit 'basic'.</p> <p>I've got an initialization file (init.php) required at the top of each of my webpages, which, among other things, connects to a MySQL database using PDO as such:</p> <pre> try { $dbh = new PDO(conn. data here); } catch(PDOException $e) { echo $e->getMessage(); } </pre> <p>So, as I understand it, on execution of this code, <code>$dbh</code> is now instantiated as a PDO object. At the bottom of my init.php file is a much of requires linking to function files, such as <code>user.func.php</code>, <code>images.func.php</code>, etc. </p> <p>The problem is whenever I need to query the database from inside one of my functions, I need to declare <code>$dbh</code> as a global before I'm able to manipulate it, like so:</p> <pre> function myFunction { global $dbh; // Here's the problem! try { $stmt = $dbh->prepare(Some SQL here); $stmt->execute(); } catch { // etc. } }</pre> <p>Now, the problem is not my understanding of <strong>why</strong> I have to declare as a global - I understand that much, but how I can avoid it. I've read some StackOverflow answers on why to avoid globals, I'm just not sure how. </p> <p>How would I go about removing <code>global $dbh</code> from my code? Would I create a database handler class and pass my connection settings to the constructor method each time I instantiate it and use that instead? (Seems a bit redundant).</p> <p>Not really sure how to replace my use of global variables, so help I can understand is definitely appreciated! </p>

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