每个实例的数据库中的整数的随机默认值? [英] Random default value for integer in database for each instance?
问题描述
我使用此系统在我的rails应用程式中投票内容: https:// github。 com / twitter / activerecord-reputation-system
有一种方法可以为任何可选项目设置一个随机数。 p>
如果我存储像rand(5..12),它只会选择一个随机默认值一次,如何获得一个随机默认值为每个不同的行或字段?
create_tablers_evaluations,:force => true do | t |
t.stringreputation_name
t.integersource_id
t.stringsource_type
t.integertarget_id
t.stringtarget_type
t.floatvalue,:default => 0.0
t.datetimecreated_at,:null => false
t.datetimeupdated_at,:null => false
end
使用 before_create 过滤器。
class RsEvaluation< ActiveRecord :: Base
before_create:update_value
def update_value
self.value = rand(5..12)
end
end
由于评估不是您的自己的模型,但一个从库,尝试打开类和修补它:
模块信誉系统
类评价< ActiveRecord :: Base
before_create:update_value
def update_value
self.value = rand(5..12)
end
end
end
这将放在 config / initializers
文件夹。
I'm using this system for voting content in my rails app: https://github.com/twitter/activerecord-reputation-system
Is there a way to make the default score for any votable item some random number for each instance.
If I store something like rand(5..12) it will only pick a random default value one time, how do I get a random default value for every different row or field?
create_table "rs_evaluations", :force => true do |t|
t.string "reputation_name"
t.integer "source_id"
t.string "source_type"
t.integer "target_id"
t.string "target_type"
t.float "value", :default => 0.0
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
Use a before_create filter.
class RsEvaluation < ActiveRecord::Base
before_create :update_value
def update_value
self.value = rand(5..12)
end
end
However; Since Evaluation is not your own model, but one from a library, try opening the class and patching it:
module ReputationSystem
class Evaluation < ActiveRecord::Base
before_create :update_value
def update_value
self.value = rand(5..12)
end
end
end
This would be placed in your config/initializers
folder.
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