<?php
ini_set('display_startup_errors',1);
ini_set('display_errors',1);
error_reporting(-1);

class App
{
    const DB_HOST = '127.0.0.1';
    const DB_USERNAME = 'root';
    const DB_PASSWORD = 'root';

    public function run() {
        echo 'Prefix: ' . $this->_getPrefix('ftf');
    }

    protected function _getPrefix($dbname) {
        $db = new PDO("mysql:host=".SELF::DB_HOST.";dbname=$dbname",SELF::DB_USERNAME,SELF::DB_PASSWORD);
        $sql = 'SHOW tables like :config';
        $q = $db->prepare($sql);
        $q->bindValue(':config', '%core_config_data%');
        $q->execute();
        $data = $q->fetchAll();
        $data = explode("core_config_data", $data[0][0]);

        return $data[0];
    }
}

$app = new App();
$app->run();