I have a database table with a certain field which should be impossible to update once it has been inserted to the database. How do I tell my model that it shouldn't allow updating of a certain field?
我有一个带有某个字段的数据库表，一旦插入数据库就不可能更新。如何告诉我的模型它不应该允许更新某个字段？
2 个解决方案
#1
45
You want to use attr_readonly:
你想使用attr_readonly：
Attributes listed as readonly will be used to create a new record but update operations will ignore these fields.
列为readonly的属性将用于创建新记录，但更新操作将忽略这些字段。
class Customer < ActiveRecord::Base
attr_readonly :your_field_name
end
#2
2
And that field is always and by definition "correct" (i.e. an accurate representation of reality) at the time of insertion ?
在插入时，该字段总是按照定义“正确”（即准确表示现实）？
No user ever makes a mistake when entering that field for the first (and in your scheme : only) time ?
在第一个（以及在您的方案中：仅）时间输入该字段时，没有用户犯过错误？
#1
45
You want to use attr_readonly:
你想使用attr_readonly：
Attributes listed as readonly will be used to create a new record but update operations will ignore these fields.
列为readonly的属性将用于创建新记录，但更新操作将忽略这些字段。
class Customer < ActiveRecord::Base
attr_readonly :your_field_name
end
#2
2
And that field is always and by definition "correct" (i.e. an accurate representation of reality) at the time of insertion ?
在插入时，该字段总是按照定义“正确”（即准确表示现实）？
No user ever makes a mistake when entering that field for the first (and in your scheme : only) time ?
在第一个（以及在您的方案中：仅）时间输入该字段时，没有用户犯过错误？