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Create unique constraint with null columns
...or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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Stack smashing detected
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Stack Smashing here is actually caused due to a protection mechanism used by gcc to detect buffer overflow errors. For example in the following snippet:
#include <stdio.h>
void func()
{
char array[10];
gets(array);
}
int main(int argc,...
How to extract a git subdirectory and make a submodule out of it?
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Nowadays there's a much easier way to do it than manually using git filter-branch: git subtree
Installation
NOTE git-subtree is now part of git (if you install contrib) as of 1.7.11, so you might already have it installed. You may check by executing git subtree.
To install...
Python: fastest way to create a list of n lists
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The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edi...
powershell 2.0 try catch how to access the exception
...tch [Net.WebException] {
$_ | fl * -Force
}
I think it will give you all the info you need.
My rule: if there is some data that is not displayed, try to use -force.
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Sort Go map values by keys
...tween runs of the program. In practice, not only is it undefined, it's actually intentionally randomized. This is because it used to be predictable, and the Go language developers didn't want people relying on unspecified behavior, so they intentionally randomized it so that relying on this behavior...
How should strace be used?
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Strace Overview
strace can be seen as a light weight debugger. It allows a programmer / user to quickly find out how a program is interacting with the OS. It does this by monitoring system calls and signals.
Uses
Good for when you don't have source code or don't want to be bothered to real...
HTML for the Pause symbol in audio and video control
...luding:
| | - two standard (bolded) vertical bars.
▋▋ - &#9611; and another&#9611;
▌▌ - &#9612; and another&#9612;
▍▍ - &#9613; and another&#9613;
▎▎ - &#9614; and another&#9614;
❚❚ - &#10074; and another &#10074;
I may have miss...
DirectX SDK (June 2010) Installation Problems: Error Code S1023
I seem to be having some problems installing the DirectX SDK. Everything seems to be going well during the install, but at the end I get the message:
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Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...