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Type:
Task
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Resolution: Done
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Affects Version/s: None
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Component/s: None
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None
I just ran into a weird issue.
I have to play with object, retrieving only their id upon some conditions to build a main request. And then I display the corresponding results.
class Product has_and_belongs_to_many :components, inverse_of: nil end class Component end class Component::Memory < Component field :quantity, type: Integer end
Let say I have a Product with a Component::Memory.
I want to retrieve the ids of some Component::Memory (there are many other types of components) to use them to query for Products. Well. But in my views, later, I have to effectively retrieve the Component::Memory through the relation.
And it seems that the Component::Memory are loaded into the IdentityMap by the only request and when accessing to one through a relation accessor in Product for example, it looks in the IdentityMap, found it, and use it. But it is incomplete because of the only that restrained the attributes retrieved.
The evidence can be made in the console:
[1] pry(main)> Component::Memory.all.only(:_id).entries => [#<Component::Memory _id: 5003d8c5f581f90113000001, _type: "Component::Memory", created_at: nil, updated_at: nil, quantity: nil, type: nil>, #<Component::Memory _id: 50052142f581f9db17000001, _type: "Component::Memory", created_at: nil, updated_at: nil, quantity: nil, type: nil>] [2] pry(main)> Product.first.components.last.quantity => nil
whereas :
[3] pry(main)> Component::Memory.all.entries => [#<Component::Memory _id: 5003d8c5f581f90113000001, _type: "Component::Memory", created_at: 2012-07-16 09:03:44 UTC, updated_at: 2012-07-16 09:03:44 UTC, quantity: 1024, type: :ddr2>, #<Component::Memory _id: 50052142f581f9db17000001, _type: "Component::Memory", created_at: 2012-07-17 08:24:52 UTC, updated_at: 2012-07-17 08:24:52 UTC, quantity: 2048, type: :ddr2>]
When identity_map is set to false, it works as expected.
mongoid (3.0.1) - moped (1.1.1) - origin (1.0.4)