用户定义的属性和非用户定义的属性有什么区别?
我的客户属性定义如下: $customerSetup->addAttribute(Customer::ENTITY, "attr_code", [ "type" => "varchar", "backend" => "", "label" => "Attribute Label", "input" => "text", "source" => "Magento\Eav\Model\Entity\Attribute\Source\Table", "visible" => true, "required" => false, "default" => "", "frontend" => "", "unique" => false, "note" => "", 'system' => 0, 'user_defined' => true ]); 我的问题是:如果设置user_defined为,该属性有什么区别false?在哪种情况下应该设置user_defined为true或false?