public function initialize()
	{
		//throw exception if no database type has been set
		if( ! $this->type )
		{
			//Throw exception
			throw new DbException("Invalid database type provided");
			
		}

		//check the type of  database provided returning instance
		//set the parameter to check in switch clause
		switch ($this->type ) 
		{
			case 'mysql':

				return new MySQL($this->options);

				break;
			
			default:

				throw new DbException("Valid database type provided");
				

				break;
		}

	}