CSV到DataMapper导入

Question

这可能很简单，但我对Ruby和活动记录颇为陌生。

我有一个数据库的CSV转储，我试图使用DataMapper导入到数据库。我无法理解我应该在模型中定义哪种类型的关系，以便它与所定义的CSV匹配。

下面是我从CSV得到了什么数据：

Stages: 
id 
staff_id 
project_id 
job_id 
company_id 

Projects: 
id 
company_id 

Jobs: 
id 
project_id 
company_id 

Client: 
id 

Staff: 
id 

例如：做阶段belong_to项目或者是这个的has_many关系？

Answer 1

我假设客户==公司。这里的ActiveRecord

class Stage < ActiveRecord::Base 
    belongs_to :staff 
    belongs_to :project 
    belongs_to :job 
    belongs_to :company, :class => "Client" 
end 

class Project < ActiveRecord::Base 
    belongs_to :company, :class => "Client" 
    has_many :stages 
end 

class Job < ActiveRecord::Base 
    belongs_to :project 
    belongs_to :company, :class => "Client" 
    has_many :stages 
end 

class Client < ActiveRecord::Base 
    has_many :jobs, :foreign_key => "company_id" 
    has_many :projects, :foreign_key => "company_id" 
    has_many :stages, :foreign_key => "company_id" 
end 

class Staff < ActiveRecord::Base 
    has_many :stages 
end 

这里DataMapper的一个例子为例：

class Stage 
    include DataMapper::Resource 
    property :id, Serial 
    belongs_to :staff 
    belongs_to :project 
    belongs_to :job 
    belongs_to :company, "Client" 
end 

class Project 
    include DataMapper::Resource 
    property :id, Serial 
    belongs_to :company, "Client" 
    has n, :stages 
end 

class Job 
    include DataMapper::Resource 
    property :id, Serial 
    belongs_to :project 
    belongs_to :company, "Client" 
    has n, :stages 
end 

class Client 
    include DataMapper::Resource 
    property :id, Serial 
    has n, :jobs, :foreign_key => "company_id" 
    has n, :projects, :foreign_key => "company_id" 
    has n, :stages, :foreign_key => "company_id" 
end 

class Staff 
    include DataMapper::Resource 
    property :id, Serial 
    has n, :stages 
end 

对于你应该做一个特殊的顺序导入：

1. Client，Staff，因为他们可以存在独立于所有其他型号
2. Project，它仅取决于Client
3. Job，取决于Project和Client
4. Stage，您使用的ActiveRecord或者DataMapper的取决于Staff，Project，Job和Client