Database hookup for wrapping around PDO

db.php

<?php
/**
 * Database hookup for wrapping around PDO
 *
 * @author     Soon Van - randomecho.com
 * @copyright  2013 Soon Van
 * @license    http://www.opensource.org/licenses/BSD-3-Clause
 */

class DB {

	public function execute($sql, $params = false, $single = true, $readonly = true)
	{
		if ($params === false)
		{
			$params = array();
		}

		$pdo = DB::hookup();
		$raw_sql = substr($sql, 0, 6);
		$sql = $pdo->prepare($sql);

		try
		{
			$sql->execute($params);
		}
		catch (Exception $e)
		{
			$bork_mess = $e->getMessage();

			if (cog::localhost())
			{
				cog::dump($sql);
				cog::dump($params);
			}
			else
			{
				echo 'Oh dear. Something bad happened.';
  			cog::mailer('Database call fail', $bork_mess);
			}
		}

		if ($readonly)
		{
			$result = ($single) ? $sql->fetch() : $sql->fetchAll();
		}
		else
		{
			if ($raw_sql == 'insert')
			{
				$result = $pdo->lastInsertId();
			}
			else
			{
				if ($single)
				{
					$result = ($sql->rowCount() == 1) ? true : false;
				}
				else
				{
					$result = $sql->rowCount();
				}
			}
		}

		return $result;
	}

	public function hookup()
	{
		if ( ! class_exists('PDO'))
		{
			cog::mailer('PDO not loaded');
			echo 'Temporarily cannot connect to the database. Working on it.';
		}

		try
		{
			$pdo = new PDO('mysql:host='.DB_SERVER.';dbname='.DB_DATABASE, DB_USERNAME, DB_PASSWORD, array(PDO::ATTR_PERSISTENT => true));
			$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
			$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
			$pdo->exec('set names utf8');

			return $pdo;
		}
		catch (PDOException $e)
		{
			$bork_mess = $e->getMessage();

			if ( ! cog::localhost())
			{
				cog::mailer('Database fail', $bork_mess);
				$bork_mess = 'That is just not quite cricket.';
			}

			cog::dump("Error: " . $bork_mess, 1);
		}
	}

	function unhook($pdo)
	{
		$pdo = null;
	}

}