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Why does NULL = NULL evaluate to false in SQL server
... in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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Getting number of elements in an iterator in Python
...s are in an iterator in Python, in general, without iterating through each and counting?
16 Answers
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How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
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Why doesn't c++ have &&= or ||= for booleans?
Is there a "very bad thing" that can happen &&= and ||= were used as syntactic sugar for bool foo = foo && bar and bool foo = foo || bar ?
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Why use apparently meaningless do-while and if-else statements in macros?
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The do ... while and if ... else are there to make it so that a
semicolon after your macro always means the same thing. Let's say you
had something like your second macro.
#define BAR(X) f(x); g(x)
Now if you were to use BAR(X); in an if ...
Visual Studio displaying errors even if projects build
I have a problem with Visual Studio on a C# solution. It displays totally random errors, but the projects build. Right now, I have 33 files with errors, and I can see red squiggly lines in all of them.
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How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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What's the difference between size_t and int in C++?
...pe size_t where I would have used a simple int . What's the difference, and why size_t should be better?
5 Answers
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How to automatically add user account AND password with a Bash script?
I need to have the ability to create user accounts on my Linux (Fedora 10) and automatically assign a password via a bash script(or otherwise, if need be).
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