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Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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Why does Decimal.Divide(int, int) work, but not (int / int)?
How come dividing two 32 bit int numbers as ( int / int ) returns to me 0 , but if I use Decimal.Divide() I get the correct answer? I'm by no means a c# guy.
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What to use instead of “addPreferencesFromResource” in a PreferenceActivity?
I just noticed the fact that the method addPreferencesFromResource(int preferencesResId) is marked deprecated in Android's documentation ( Reference Entry ).
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How do I kill background processes / jobs when my shell script exits?
I am looking for a way to clean up the mess when my top-level script exits.
13 Answers
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Fast ceiling of an integer division in C / C++
Given integer values x and y , C and C++ both return as the quotient q = x/y the floor of the floating point equivalent. I'm interested in a method of returning the ceiling instead. For example, ceil(10/5)=2 and ceil(11/5)=3 .
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In C, how should I read a text file and print all strings
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The simplest way is to read a character, and print it right after reading:
int c;
FILE *file;
file = fopen("test.txt", "r");
if (file) {
while ((c = getc(file)) != EOF)
putchar(c);
fclose(file);
}
c is int above, since EOF is a negative number, and a pl...
How can I use Timer (formerly NSTimer) in Swift?
...iewDidLoad()
// Swift block syntax (iOS 10+)
let timer = Timer(timeInterval: 0.4, repeats: true) { _ in print("Done!") }
// Swift >=3 selector syntax
let timer = Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)
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how to read System environment variable in Spring applicationContext
How to read the system environment variable in the application context?
11 Answers
11
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Mercurial error: abort no username supplied
Problem on WindowsXP (likely will happen on all Win installs), first time using Mercurial. I found the answer in an inobvious place so I'm asking/answering the question myself so others don't have to search like I did.
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What is the difference between MacVim and regular Vim?
I'm reasonably new to OS X, but I'm familiar with Vim from using it in various *nix systems. I've seen many people recommend running MacVim over Vim in the terminal. Can anyone tell me what differences there are between MacVim and regular Vim?
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