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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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I've found my software as cracked download on Internet, what to do?
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edited Sep 20 '10 at 13:05
community wiki
2 r...
Why can't I forward-declare a class in a namespace using double colons?
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bash assign default value
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Not just shorter, but less error-prone: VERY_LONG_VARIABLE_NAME=${VERY_LOGN_VARIABLE_NAME:-hello}. Oops.
– chepner
Aug 17 '14 at 13:40
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How to keep the local file or the remote file during merge using Git and the command line?
...ge modification using vimdiff, but, assuming I just know that the entire file is good to keep or to throw away, how do I do that?
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Difference between abstract class and interface in Python
...xpected to supply."""
def aMethod( self ):
raise NotImplementedError( "Should have implemented this" )
Because Python doesn't have (and doesn't need) a formal Interface contract, the Java-style distinction between abstraction and interface doesn't exist. If someone goes through the ef...
In Python, using argparse, allow only positive integers
...lue = int(value)
if ivalue <= 0:
raise argparse.ArgumentTypeError("%s is an invalid positive int value" % value)
return ivalue
parser = argparse.ArgumentParser(...)
parser.add_argument('foo', type=check_positive)
This is basically just an adapted example from the perfect_square...
GCM with PHP (Google Cloud Messaging)
...Actually send the request
$result = curl_exec($ch);
// Handle errors
if (curl_errno($ch)) {
echo 'GCM error: ' . curl_error($ch);
}
// Close curl handle
curl_close($ch);
// Debug GCM response
echo $result;
}
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Quicksort vs heapsort
Both quicksort and heapsort do in-place sorting. Which is better? What are the applications and cases in which either is preferred?
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What is a “surrogate pair” in Java?
I was reading the documentation for StringBuffer , in particular the reverse() method. That documentation mentions something about surrogate pairs . What is a surrogate pair in this context? And what are low and high surrogates?
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