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Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
I have a problem when data is null and the warning has appear when the result is display.
How to solve this problem?. How to change the null data to 0 when no data in the table?.
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When should one use a spinlock instead of mutex?
... a thread tries to lock a mutex and it does not succeed, because the mutex is already locked, it will go to sleep, immediately allowing another thread to run. It will continue to sleep until being woken up, which will be the case once the mutex is being unlocked by whatever thread was holding the lo...
In C#, why is String a reference type that behaves like a value type?
A String is a reference type even though it has most of the characteristics of a value type such as being immutable and having == overloaded to compare the text rather than making sure they reference the same object.
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Why is it possible to recover from a StackOverflowError?
I'm surprised at how it is possible to continue execution even after a StackOverflowError has occurred in Java.
5 Answers...
C++11 rvalues and move semantics confusion (return statement)
...p;rval_ref = return_vector();
The first example returns a temporary which is caught by rval_ref. That temporary will have its life extended beyond the rval_ref definition and you can use it as if you had caught it by value. This is very similar to the following:
const std::vector<int>& r...
How does libuv compare to Boost/ASIO?
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Scope
Boost.Asio is a C++ library that started with a focus on networking, but its asynchronous I/O capabilities have been extended to other resources. Additionally, with Boost.Asio being part of the Boost libraries, its scope is slightly na...
abort, terminate or exit?
... the exceptions you can't handle in main() and simply return from there. This means that you are guaranteed that stack unwinding happens correctly and all destructors are called. In other words:
int main() {
try {
// your stuff
}
catch( ... ) {
return 1; // or whatever
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Thread context switch Vs. process context switch
Could any one tell me what is exactly done in both situations? What is the main cost each of them?
10 Answers
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Check if a string matches a regex in Bash script
One of the arguments that my script receives is a date in the following format: yyyymmdd .
5 Answers
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