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Best way to select random rows PostgreSQL
I want a random selection of rows in PostgreSQL, I tried this:
12 Answers
12
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When should I use a struct instead of a class?
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MSDN has the answer:
Choosing Between Classes and Structures.
Basically, that page gives you a 4-item checklist and says to use a class unless your type meets all of the criteria.
Do not define a structure unless the
type has all of the following
characterist...
Aren't promises just callbacks?
...d error callback for all occurred exceptions.
Not to mention having to convert things to promises.
That's quite trivial actually with good promise libraries, see How do I convert an existing callback API to promises?
s...
What is the real overhead of try/catch in C#?
So, I know that try/catch does add some overhead and therefore isn't a good way of controlling process flow, but where does this overhead come from and what is it's actual impact?
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Java: random long number in 0
Random class has a method to generate random int in a given range. For example:
16 Answers
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What is the fastest integer division supporting division by zero no matter what the result is?
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Inspired by some of the comments I got rid of the branch on my Pentium and gcc compiler using
int f (int x, int y)
{
y += y == 0;
return x/y;
}
The compiler basically recognizes that it can use a condition flag of the test in the addition.
As per request the assembly:
.globl...
BSS段、数据段、代码段、堆与栈 剖析 - C/C++ - 清泛网 - 专注C/C++及内核技术
...区。
【例一】
用cl 编译两个小程序如下：
程序1:
int ar[30000];
void main()
{
......
}
程序2:
int ar[300000] = {1, 2, 3, 4, 5, 6 };
void main()
{
......
}
发现程序2 编译之后所得的.exe 文件比程序1 的要大得多。当下甚为不解，于...
Determining if a number is either a multiple of ten or within a particular set of ranges
...m - 1) / 10) % 2 == 1 && num <= 100)
But that's rather dense, and you might be better off just listing the options explicitly.
Now that you've given a better idea of what you are doing, I'd write the second one as:
int getRow(int num) {
return (num - 1) / 10;
}
if (ge...
How do I show the value of a #define at compile-time?
...n in the gcc online documentation.
How it works:
The preprocessor understands quoted strings and handles them differently from normal text. String concatenation is an example of this special treatment. The message pragma requires an argument that is a quoted string. When there is more than one com...
Populate a Razor Section From a Partial
...red by a partial at the bottom of the page with the rest of the Javascript and not in the middle of the page where the partial is rendered.
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