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Count number of records returned by group by
...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically.
– Joe Aldrich
Sep 20 '17 at 13:33
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How to compare type of an object in Python?
Basically I want to do this:
14 Answers
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Abstract classes in Swift Language
... importantly, notice that there is no dynamic dispatch. When logSalary is called on the instance that is stored as a SoftwareEngineer it calls the overridden version of the method. When logSalary is called on the instance after it has been cast to an Employee, it calls the original implementation (i...
What is the best way to compute trending topics or tags?
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This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...
Append an object to a list in R in amortized constant time, O(1)?
...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
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What is the difference between a mutable and immutable string in C#?
...pe
To "effect a change" on a string represented as a C# String, you actually create a new String object. The original String is not changed ... because it is unchangeable.
In most cases it is better to use String because it is easier reason about them; e.g. you don't need to consider the possib...
Why do I need an IoC container as opposed to straightforward DI code? [closed]
...ain can become nested, and it quickly becomes unwieldy to wire them up manually. Even with factories, the duplication of your code is just not worth it.
IoC containers can be complex, yes. But for this simple case I've shown it's incredibly easy.
Okay, let's justify this even more. Let's say ...
C++ Redefinition Header Files (winsock2.h)
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I'm not including <windows.h> at all, I know <winsock2.h> does its for me.
– akif
Sep 3 '09 at 11:26
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How do I get the real .height() of a overflow: hidden or overflow: scroll div?
...qual to the minimum clientHeight the element would require in order to fit all the content in the viewpoint without using a vertical scrollbar. It includes the element padding but not its margin.
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Python != operation vs “is not”
...right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is operation.
You use is (and is not) for singletons, like None, where you don't care about objects that might want to pretend to be None or where you want to protect against object...