gistfile1.txt

<?php

namespace ActivismeBe\Dataset\Adapters;

use PDO;
use PDOException;
use Dotenv\Dotenv;

/**
 * Class MysqlAdapter
 *
 * @package ActivismeBe\Dataset\Adapters
 */
class MysqlAdapter
{
    /**
     * Provided variable for the database connection.
     * @var PDO
     */
    private $dbh;

    /**
     * Provided variable for pdo errors
     *
     * @var string
     */
    private $error;

    /**
     * Provided variable for the queries.
     *
     * @var $stmt
     */
    private $stmt;

    /**
     * MysqlAdapter constructor.
     *
     * @return MySQL database connection
     * @throws \PDOException
     */
    public function __construct()
    {
        $dotenv = new Dotenv(__DIR__ . '/../../');
        $dotenv->overload();

        $dsn     = 'mysql:host=' . getenv('DB_HOST') . ';dbname=' . getenv('DB_NAME');
        $options = [PDO::ATTR_PERSISTENT => true, PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION];

        try { // Create a new PDO instance
            $this->dbh = new PDO($dsn, getenv('DB_USER'), getenv('DB_PASS'), $options);
        } catch (PDOException $e) { // Catch any errors
            $this->error = $e->getMessage();
        }
    }

    /**
     * [Prepare]
     *
     * The query method also introduces the PDO:prepare statement.
     *
     * The Prepare function allows you to vind values in your SQL Statements. This
     * is important because it take away the threat of SQL Injection vecause you are
     * no longer having manually include the parameters into the query string.
     *
     * Using the prepare function will also improve performance when rynning the
     * same query with different parameters multiple times.
     *
     * @param  string $query The database query.
     * @return void
     */
    public function query($query)
    {
        $this->stmt = $this->dbh->prepare($query);
    }

     /**
      * [Bind]
      *
      * The next method we will be looking at is the bind method. In order to prepare
      * our SQL queries, we need to bind the inputs with the placeholders we put in
      * place. This is what the Bind method used for.
      *
      * The main part of this method is based upon the PDOStatement::bindValue PDO
      * method.
      *
      * @param  string  $param  Is the actual placeholder value that we will be using in out SQL statement.
      * @param  string  $value  Is the actual param taht we want to bind to the placeholder.
      * @param  mixed   $type   Is the datatype of the parameter, example string. default = null
      * @return mixed
      */
     public function bind($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);
     }

     /**
      * [Execute]
      *
      * The next method we will be look at is the PDOStatement::execute. The execute
      * method executes the prepared statement.
      */
     public function execute()
     {
         return $this->stmt->execute();
     }
}

http://culttt.com/2012/10/01/roll-your-own-pdo-php-class/