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How to create a unique index on a NULL column?
...k, and normalization usually involves the addition of several (non-entity) extra tables to establish relationships between the entities.
Let's work a basic example considering only one "unique nullable column", it's easy to expand it to more such columns.
Suppose we the information represented by ...
Qt events and signal/slots
...resents a new abstraction: a widget that acts like a button, but with some extra functionality. We added this functionality very conveniently:
Since we reimplemented a virtual, our implementation automatically became encapsulated in our class. If Qt's designers had made keyPressEvent a signal, we ...
Should I implement __ne__ in terms of __eq__ in Python?
... work (assuming SQLAlchemy knows how to insert MyClassWithBadNE into a SQL string at all; this can be done with type adapters without MyClassWithBadNE having to cooperate at all), passing the expected proxy object to filter, while:
results = session.query(MyTable).filter(MyClassWithBadNE() != MyTa...
How to access the correct `this` inside a callback?
... that adds meaning, or some preceding and following information that gives extra meaning. The term "context" is used in ECMAScript to refer to execution context, which is all the parameters, scope, and this within the scope of some executing code.
This is shown in ECMA-262 section 10.4.2:
Set the T...
What is the difference between 'classic' and 'integrated' pipeline mode in IIS7?
...mply say that in Classic mode IIS 7.x works just as IIS 6 and you dont get extra benefits out of IIS 7.x features.
In integrated mode IIS and ASP.Net are tightly coupled rather then depending on just two DLLs on Asp.net as in case of classic mode.
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Private vs Protected - Visibility Good-Practice Concern [closed]
... sure.
There are two cases you want to extend a class:
You want to add extra functionality to a base class
You want to modify existing class that's outside the current package (in some libraries perhaps)
There's nothing wrong with private fields in the first case. The fact that people are abus...
Instance variables vs. class variables in Python
...f time savings.
However, if you insist on class attributes, you need that extra lookup. Or, your other alternative is to refer to the object via the class instead of the instance, e.g., MyController.path instead of self.path. That's a direct lookup which will get around the deferred lookup, but as ...
Private virtual method in C++
...anup()s in the chain, the argument falls apart. Or are you recommending an extra virtual function for each descendant in the chain? Ick. Even Herb Sutter allowed protected virtual functions as a loophole in his guideline #3. Anyway, without some actual code you'll never convince me.
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Bash tool to get nth line from a file
...he trick, but I've been wondering if there's a Bash tool that specifically extracts a line (or a range of lines) from a file.
...
Making 'git log' ignore changes for certain paths
...ath-match checks on individual paths under the directory would cause those extra paths to be filtered out, the only difference from using the wrong function was unnecessary computation.
The second of those bad calls to do_match_pathspec() was involved -- via either direct movement or via copying+edi...