private function _prepareColumnArgument($column)
	{
		if(!is_string($column) && !$column instanceof SqlFunctionInterface)
		{
			throw new \InvalidArgumentException('Argument 1 passed is not the expected type!');
		}
		if($column instanceof SqlFunctionInterface || $column === '*')
		{
			$this->columnName = (string)htmlentities($column, ENT_QUOTES);
		}
		else
		{
			$this->columnName = '`' . htmlentities($column, ENT_QUOTES) . '`';
		}
	}