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Best way to select random rows PostgreSQL
...e or the recursion may run dry before the limit is reached - or we have to start with a large enough buffer which defies the purpose of optimizing performance.
Duplicates are eliminated by the UNION in the rCTE.
The outer LIMIT makes the CTE stop as soon as we have enough rows.
This query is care...
Math - mapping numbers
...de to get the ratio between the sizes of the two ranges, then subtract the starting value of your inital range, multiply by the ratio and add the starting value of your second range. In other words,
R = (20 - 10) / (6 - 2)
y = (x - 2) * R + 10
This evenly spreads the numbers from the first range ...
How to create a Menubar application for Mac
...
I've found Codebox's Popup to be a great starting point. It is ripe for forking on Github.
Though it works nicely, they do note on their site...
P. S. In Lion, Apple is adding a new class for popovers like in iOS.
So, after OS X 10.7 is released, you would...
bool operator ++ and --
... before this is an issue. With -- though it will only result in false if I started with a value of 1 for true, or started with 0 and used ++ precisely once before.
This is different if we start with a value that is just a few below 0. Indeed, in such a case we might want ++ to result in the false va...
Relational table naming convention [closed]
I'm starting a new project and would like to get my table- and column names right from the start. For example I've always used plural in table names but recently learned singular is correct.
...
time.sleep — sleeps thread or process?
...3):
print x
time.sleep(5)
def run():
worker().start()
waiter().start()
Which will print:
>>> thread_test.run()
0
100
>>> 1
2
3
4
5
101
6
7
8
9
10
102
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What is the equivalent to a JavaScript setInterval/setTimeout in Android/Java?
...n("Seconds passed: " + mSecondsPassed);
}
};
private void start() {
mTimer.scheduleAtFixedRate(mTask, 1000, 1000);
}
public static void main(String[] args) {
Clock c = new Clock();
c.start();
}
}
...
Android search with Fragments
...en the user executes a search in the search dialog or widget, the
system starts your searchable activity and delivers it the search
query in an Intent with the ACTION_SEARCH action. Your searchable
activity retrieves the query from the intent's QUERY extra, then
searches your data and presen...
What are the downsides to using Dependency Injection? [closed]
...h needs slightly different dependencies - tough, you're locked in. Time to start writing some adaptors for those dependencies instead (and a bit more overhead and another layer of abstraction).
– Steve314
Feb 10 '11 at 17:59
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Chrome: Uncaught SyntaxError: Unexpected end of input
...ut what exactly is wrong with my json request. i just had no idea where to start debugging. if i may ask how did you determine the root cause
– dlaurent86
Aug 29 '10 at 13:52
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