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Foreign keys in mongo?

...his: class Student include Mongoid::Document field :name embeds_many :addresses embeds_many :scores end class Address include Mongoid::Document field :address field :city field :state field :postalCode embedded_in :student end class Score include Mongoi...
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Check if OneToOneField is None in Django

... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
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Rails params explained?

...e "1" and params[:boo] would be "octopus". In HTTP/HTML, the params are really just a series of key-value pairs where the key and the value are strings, but Ruby on Rails has a special syntax for making the params be a hash with hashes inside. For example, if the user's browser requested http://w...
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Optional query string parameters in ASP.NET Web API

...ect using [FromUri] doesn't directly answer the original question. It basically says populate these models with the values from the Uri. The models properties would need to be nullable or a reference type in order for them to support being optional. Added additional information. ...
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Matplotlib: “Unknown projection '3d'” error

...e you using? (Try running: python -c 'import matplotlib; print matplotlib."__version__") I'm guessing you're running version 0.99, in which case you'll need to either use a slightly different syntax or update to a more recent version of matplotlib. If you're running version 0.99, try doing this in...
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Python - abs vs fabs

...e about complex numbers. Out of interest, what other classes of things can __builtin__.abs() be successfully applied to? – NPE May 27 '12 at 7:31 ...
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Scala: Nil vs List()

In Scala, is there any difference at all between Nil and List() ? 3 Answers 3 ...
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Do declared properties require a corresponding instance variable?

... In your interface, you can formally declare an instance variable between the braces, or via @property outside the braces, or both. Either way, they become attributes of the class. The difference is that if you declare @property, then you can implement usin...
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Why can't yield return appear inside a try block with a catch?

...ty. I suspect there are very, very few times where this restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant. There are a few things like this that I've already encountered: Attributes not being able to be generic Inabil...
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Does order of where clauses matter in SQL?

Let's say I have a table called PEOPLE having 3 columns ID, LastName, FirstName , none of these columns are indexed. LastName is more unique, and FirstName is less unique. ...