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PostgreSQL: Can you create an index in the CREATE TABLE definition?
I want to add indexes to some of the columns in a table on creation. Is there are way to add them to the CREATE TABLE definition or do I have to add them afterward with another query?
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When should you not use virtual destructors?
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There is no need to use a virtual destructor when any of the below is true:
No intention to derive classes from it
No instantiation on the heap
No intention to store in a pointer of a superclass
No specific reason to avoid it unless you are really so pressed for memory.
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How to keep a git branch in sync with master
At the moment git is doing my head in, I cannot come up with the best solution for the following.
6 Answers
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How to catch integer(0)?
...of printing a zero length vector (an integer one), so you could test for a being of length 0:
R> length(a)
[1] 0
It might be worth rethinking the strategy you are using to identify which elements you want, but without further specific details it is difficult to suggest an alternative strategy....
Can someone explain Microsoft Unity?
I've been reading the articles on MSDN about Unity (Dependency Injection, Inversion of Control), but I think I need it explained in simple terms (or simple examples). I'm familiar with the MVPC pattern (we use it here), but I just can't really grasp this Unity thing yet, and I think it's the next st...
Assignment inside lambda expression in Python
I have a list of objects and I want to remove all objects that are empty except for one, using filter and a lambda expression.
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What does the [Flags] Enum Attribute mean in C#?
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The [Flags] attribute should be used whenever the enumerable represents a collection of possible values, rather than a single value. Such collections are often used with bitwise operators, for example:
var allowedColors = MyColor.Red | MyCol...
Optional Parameters with C++ Macros
...etting optional parameters with C++ Macros? Some sort of overloading would be nice too.
14 Answers
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Count number of objects in list [closed]
R function that will return the number of items in a list?
5 Answers
5
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Loop through an array in JavaScript
In Java you can use a for loop to traverse objects in an array as follows:
40 Answers
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