public function like($propertyName, $propertyValue) {
		$parameterName = ':' . md5($propertyName . '#' . count($this->where));
		$this->where[] = '(`' . $propertyName . '` LIKE ' . $parameterName . ')';
		$this->parameterMap[$parameterName] = '%' . $propertyValue . '%';

		return $this;
	}