在 Rails 中支持外键约束
在Ruby on Rails中,迁移时如何添加外键约束?
In Ruby on Rails, how to add foreign key constraint in migration?
推荐答案
AFAIK,没有任何内置支持,但是有 几个插件可以帮助你.您也可以手动将它们添加到迁移文件中,只需使用执行方法即可,例如(来自 Rails API 的示例):
AFAIK, there isn't any built-in support for that, but there are several plugins that help you with that. You can also add them manually to your migration files, just use the execute method for that, e.g. (sample from Rails API):
class MakeJoinUnique < ActiveRecord::Migration
def self.up
execute "ALTER TABLE `pages_linked_pages` ADD UNIQUE `page_id_linked_page_id` (`page_id`,`linked_page_id`)"
end
def self.down
execute "ALTER TABLE `pages_linked_pages` DROP INDEX `page_id_linked_page_id`"
end
end
相关文章