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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
How to prompt for user input and read command-line arguments [closed]
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You don't have to use str() in print concatenation since all entered data will be str(ing) type by default (even numbers).
– Goujon
Nov 8 '17 at 11:50
add a ...
How to evaluate a math expression given in string form?
...is in a server context with user input. The executed JavaScript can access all Java classes and thus hijack your application without limit.
– Boann
Sep 21 '15 at 11:08
4
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Is it good practice to NULL a pointer after deleting it?
...d to achieve in practice. I prefer a masked double delete bug over UB.
Finally, a sidenote regarding managing object allocation, I suggest you take a look at std::unique_ptr for strict/singular ownership, std::shared_ptr for shared ownership, or another smart pointer implementation, depending on yo...
How to determine if a type implements an interface with C# reflection
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@PierreArnaud: IsAssignableFrom does eventually calls GetInterfaces, so probably your test checked the GetInterfaces first and IsAssignable after. That is because GetInterfaces caches it's results so the first invocation costs more
– Panos Theof
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Will iOS launch my app into the background if it was force-quit by the user?
... Unlike the application:didReceiveRemoteNotification: method, which is
called only when your app is running in the foreground, the system
calls this method when your app is running in the foreground or
background. In addition, if you enabled the remote notifications
background mode, the sys...
SplitView like Facebook app on iPhone
...ein10/SlidingMenu for Android implementation. It's way more efficient than all other alternative..
– ChristopheCVB
Feb 20 '13 at 15:40
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sho...
How to sort a HashSet?
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Add all your objects to the TreeSet, you will get a sorted Set. Below is a raw example.
HashSet myHashSet = new HashSet();
myHashSet.add(1);
myHashSet.add(23);
myHashSet.add(45);
myHashSet.add(12);
TreeSet myTreeSet = new TreeS...
How do I horizontally center an absolute positioned element inside a 100% width div? [duplicate]
...xample below, #logo is positioned absolutely and I need it to be horizontally centered within #header . Normally, I would do a margin:0 auto for relatively positioned elements but I am stuck here. Can someone show me the way?
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Using Mockito to test abstract classes
I'd like to test an abstract class. Sure, I can manually write a mock that inherits from the class.
11 Answers
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