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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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How to get a list of installed android applications and pick one to run
...sked a similar question to this earlier this week but I'm still not understanding how to get a list of all installed applications and then pick one to run.
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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...
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...
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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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...
PHP: How to handle
.../>), the position of the child element in the text, etc. LIBXML_NOCDATA converts CDATA nodes into text nodes, but doesn't fix the rest.
– IMSoP
Feb 7 '15 at 15:54
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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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How do I change the color of the text in a UIPickerView under iOS 7?
...tedString *)pickerView:(UIPickerView *)pickerView attributedTitleForRow:(NSInteger)row forComponent:(NSInteger)component
{
NSString *title = @"sample title";
NSAttributedString *attString =
[[NSAttributedString alloc] initWithString:title attributes:@{NSForegroundColorAttributeName:...
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...