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Should I index a bit field in SQL Server?
...ng a field with low cardinality (a low number of distinct values) is not really worth doing. I admit I don't know enough about how indexes work to understand why that is.
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Caveats of select/poll vs. epoll reactors in Twisted
...ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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Why are Perl 5's function prototypes bad?
...nd to expect prototypes to provide a mechanism for checking that function calls are correct: that is, that they have the right number and type of arguments. Perl's prototypes are not well-suited for this task. It's the misuse that's bad. Perl's prototypes have a singular and very different purpose:
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How to get the path of a running JAR file?
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One more note: While calling this function from the Jar, the name of the jar is appended at the end for me, therefore had to execute: path.substring(0, path.lastIndexOf("/") + 1);
– will824
Oct 5 '11 at 15:29...
How do I record audio on iPhone with AVAudioRecorder?
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Actually, there are no examples at all.
Here is my working code. Recording is triggered by the user pressing a button on the navBar.
The recording uses cd quality (44100 samples), stereo (2 channels) linear pcm. Beware: if you wa...
Using boolean values in C
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@NoBody Using a smaller type can save on memory, but it might not make it any faster. Often, it's faster to use the processor's native word size instead of a smaller size as it could require the compiler to make bit shifts to align it properly...
jQuery: checking if the value of a field is null (empty)
...ype]').val().length != 0){}
If you want to check if the element exist at all, you should do that before calling val:
var $d = $('#person_data[document_type]');
if ($d.length != 0) {
if ($d.val().length != 0 ) {...}
}
s...
Easiest way to check for an index or a key in an array?
... associative array)
[ ${array[key]+abc} ] && echo "exists"
Basically what ${array[key]+abc} does is
if array[key] is set, return abc
if array[key] is not set, return nothing
References:
See Parameter Expansion in Bash manual and the little note
if the colon is omitted, the ope...
When should you branch?
... Jan 20 '10 at 11:09
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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How do you increase the max number of concurrent connections in Apache?
...ts 200
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
First of all, whenever an apache is started, it will start 2 child processes which is determined by StartServers parameter. Then each process will start 25 threads determined by ThreadsPerChild parameter so this means 2 process can se...