protected function grammar()
		{
			if (isset($this->grammar)) return $this->grammar;

			switch (isset($this->config['grammar']) ? $this->config['grammar'] : $this->driver()) {
				case 'mysql':
					return $this->grammar = new Query\Grammars\MySQL($this);

				case 'sqlsrv':
					return $this->grammar = new Query\Grammars\SQLServer($this);

				default:
					return $this->grammar = new Query\Grammars\Grammar($this);
			}
		}