Is this a good or bad example of a class?

I'm still trying to get my head around OO PHP. I haven't tackled it for a while, but I was just having a play around and finally managed to at least get something working.

Is this a good way or a bad way to do it though? The idea is that I can run queries easier:

index.php

<?php

require("class.php");

$fetchProperties = new StdClass;

$fetchProperties->what = '*';
$fetchProperties->from = 'stories';
$fetchProperties->where = 'cat_id';
$fetchProperties->equals = 1;

$do = new getStuff();

$do->getStories($fetchProperties);

?>

PHP:

classes.php

class getStuff
{
    public function getStories($fetchProperties){
        if (isset($fetchProperties)){
            include "" . $_SERVER['DOCUMENT_ROOT'] . "/_config/db.php";
            $statement = $dbconn->prepare("
                SELECT     $fetchProperties->what
                FROM     $fetchProperties->from
                WHERE     $fetchProperties->where = :equals
            ");
            $statement->execute([
                ":equals"    =>        $fetchProperties->equals
            ]);
            $rows = $statement->fetchAll(PDO::FETCH_ASSOC);
            foreach ($rows AS $row){
                var_dump($row);
            }
        }else {
            errorResponse("Must have all variables");
        }
    }
}//End getStuff

PHP:

 

Nothing wrong with this. A few suggestions, though.

Type hinting is excellent for this kind of things.

getStories(stdClass $fetchProperties){

PHP:

This makes sure you can't pass anything unexpected.

Furthermore, I'd create a custom class for this. This way, you can pre-define the properties you want to have, and it gives you a little more control over it.

class FetchProperties
{
    public $what = '';
    // etc...
}

PHP:

 

I am guessing you are planning on building that up, I would suggest you do it correctly the first time around. The following suggestions should get you established even for complex queries:

1) Make $what an array, this way you can add/remove elements from the what as you like.
2) Make the $where an array as well to give you the ability to have multiple conditions.
3) Escape all your arguments including the what and where. I assume the reason you did it because the source is trusted, nevertheless I would suggest you do.

Finally (probably just thinking of other DB systems) you might want to separate the what, where, from into their own variables.

getStories ($from, array $what = array('*'), array $where = array());

Code (markup):