<?php
class Database {
    private $host   = "localhost";
    private $user   = "root";
    private $pass   = "123456";
    private $dbname = "test";
    private $db;
    private $error;
    private $stmt;
    public function __construct() {
        $dsn     = 'mysql:host=' . $this->host . ';dbname=' . $this->dbname;
        $options = [
            PDO::ATTR_PERSISTENT => true,
            PDO::ATTR_ERRMODE    => PDO::ERRMODE_EXCEPTION];
        try {
            $this->db = new PDO($dsn, $this->user, $this->pass, $options);
        } catch (PDOException $e) {
            $this->error = $e->getMessage();
        }
    }

    public function query($query) {
        $this->stmt = $this->db->prepare($query);
    }

    public function bind($param, $value, $type = null) {
        if (is_null($type)) {
            switch (true) {
                case is_int($value):
                    $type = PDO::PARAM_INT;
                    break;
                case is_bool($value):
                    $type = PDO::PARAM_BOOL;
                    break;
                case is_null($value):
                    $type = PDO::PARAM_NULL;
                    break;
                default:
                    $type = PDO::PARAM_STR;
            }
        }
        $this->stmt->bindValue($param, $value, $type);
    }

    public function execute() {
        return $this->stmt->execute();
    }
}
$data = new Database;
$sql  = " INSERT INTO users (name,email) VALUES (:name,:email)";
$stmt = $data->query($sql);
$stmt = $data->bind(':name', "John");
$stmt = $data->bind(':email', "google@gmail.com");
$stmt = $data->execute();