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SET versus SELECT when assigning variables?
What are the differences between the SET and SELECT statements when assigning variables in T-SQL?
4 Answers
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Retain precision with double in Java
...of 11.4.
Now, a little explanation into why this is happening:
The float and double primitive types in Java are floating point numbers, where the number is stored as a binary representation of a fraction and a exponent.
More specifically, a double-precision floating point value such as the double...
MySQL foreign key constraints, cascade delete
I want to use foreign keys to keep the integrity and avoid orphans (I already use innoDB).
3 Answers
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What does {0} mean when initializing an object?
... object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
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Max length UITextField
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With Swift 5 and iOS 12, try the following implementation of textField(_:shouldChangeCharactersIn:replacementString:) method that is part of the UITextFieldDelegate protocol:
func textField(_ textField: UITextField, shouldChangeCharacter...
C++11 emplace_back on vector?
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Yeah, spelling it out helps me understand what you meant! Good point. I agree that sometimes the generalisation is bearable when weighed against the other stuff the STL provides for us: I use that semi-often with pair... but sometimes wonder if I really gain much...
How to throw a C++ exception
I have a very poor understanding of exception handling(i.e., how to customize throw, try, catch statements for my own purposes).
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Most efficient method to groupby on an array of objects
... })
};
});
};
group.register = function(name, converter) {
return group[name] = function(data, names) {
return _.map(group(data, names), converter);
};
};
return group;
}());
DataGrouper.register("sum", function(item) {
return _....
Can an ASP.NET MVC controller return an Image?
...image through the controller (http://localhost/MyController/Image/MyImage) and through the direct URL (http://localhost/Images/MyImage.jpg) and the results were:
MVC: 7.6 milliseconds per photo
Direct: 6.7 milliseconds per photo
Note: this is the average time of a request. The average was calcul...
Is iterating ConcurrentHashMap values thread safe?
... obtain from a ConcurrentHashMap is designed to be used by a single thread and should not be passed around. This includes the syntactic sugar that the for-each loop provides.
What happens if I try to iterate the map with two threads at the same time?
It will work as expected if each of the thr...