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What is the PostgreSQL equivalent for ISNULL()
...g that it is coalesce that is in SQL standard, with isnull being an MS-specific function that essentially is coalesce with only two parameters.
– GSerg
Feb 6 '10 at 20:35
4
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What's the most efficient way to erase duplicates and sort a vector?
...with R. Pate and Todd Gardner; a std::set might be a good idea here. Even if you're stuck using vectors, if you have enough duplicates, you might be better off creating a set to do the dirty work.
Let's compare three approaches:
Just using vector, sort + unique
sort( vec.begin(), vec.end() );
ve...
Using a constant NSString as the key for NSUserDefaults
...le the second is a pointer to a constant NSString object.
It is a subtle difference. The compiler warning happens because setObject:forKey: is declared as follows:
- (void)setObject:(id)value forKey:(NSString *)defaultName;
It is expecting the defaultName argument to be of type NSString *. When ...
What is the difference between #include and #include “filename”?
In the C and C++ programming languages, what is the difference between using angle brackets and using quotes in an include statement, as follows?
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Why is String.chars() a stream of ints in Java 8?
...e should, given they do not want to make CharStream, which is reasonable, different methods instead of chars(), I would think of:
Stream<Character> chars(), that gives a stream of boxes characters, which will have some light performance penalty.
IntStream unboxedChars(), which would to be us...
How can I check if an element exists in the visible DOM?
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It seems some people are landing here, and simply want to know if an element exists (a little bit different to the original question).
That's as simple as using any of the browser's selecting method, and checking it for a truthy value (generally).
For example, if my element had an id o...
const vs constexpr on variables
Is there a difference between the following definitions?
4 Answers
4
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Using IoC for Unit Testing
...rtant. You can choose to use a DI Container to wire up the components, but if so, you are likely to need a different configuration for the container than in the full application - unless you perform a Subcutaneous Test or a full System Test, in which case you can reuse the application's configuratio...
Remove columns from DataTable in C#
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Just to clarify: This also works when the DataTable already has existing rows, not only on an empty DataTable.
– Uwe Keim
May 18 '15 at 9:26
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Storing a Map using JPA
I am wondering if it is possible using annotations to persist the attributes map in the following class using JPA2
2 Answ...