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Flask SQLAlchemy query, specify column names
... do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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What is a None value?
...n't write the sticker "F", there was already an F sticker on the None, and all you did was move it, from None to "fork". So when you type F = None, you're "reset[ting] it to its original, empty state", if we decided to treat None as meaning empty state.
I can see what he's getting at, but that's a...
Can comments be used in JSON?
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No.
The JSON should all be data, and if you include a comment, then it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be bett...
nil detection in Go
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In addition to Oleiade, see the spec on zero values:
When memory is allocated to store a value, either through a declaration or a call of make or new, and no explicit initialization is provided, the memory is given a default initialization. Each element of such a value is set to the zero valu...
Difference between jQuery parent(), parents() and closest() functions
...p) the DOM tree.
parents() method is similar to parent() but selects all the
matching elements up the DOM tree. Begins from the parent element and travels up.
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Does setting Java objects to null do anything anymore?
... object chain A->B->C, then once A is not reachable, A, B and C will all be eligible for garbage collection (assuming nothing else is referring to either B or C). There's no need, and never has been any need, to explicitly set references A->B or B->C to null, for example.
Apart from tha...
How can I provide multiple conditions for data trigger in WPF?
...D are false, and set the default to true.
– WeSam Abdallah
Oct 28 '14 at 15:47
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Adaptive segue in storyboard Xcode 6. Is push deprecated?
...e. I am using Xcode 6 beta 2 and to test I used the single view template (calling the pre made view controller in IB ‘VC_A’). I then added another view controller (‘VC_B’). I then added a button on VC_A to show VC_B and another from VC_B back to VC_A. When I add a navigation controller as th...
MVVM in WPF - How to alert ViewModel of changes in Model… or should I?
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RaisePropertyChanged("ViewModelCopyOfSomeProperty");
}
But typically this is only needed if more than one object will be making changes to the Model's data, which is not usually the case.
If you ever have a case where you don't actually have a reference to your Model property to attach t...
Why does the C# compiler not fault code where a static method calls an instance method?
The following code has a static method, Foo() , calling an instance method, Bar() :
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