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What is the difference between char, nchar, varchar, and nvarchar in SQL Server?
...torage space for number of characters you specify even if you don't use up all that space.
varchar and nvarchar are variable-length which will only use up spaces for the characters you store. It will not reserve storage like char or nchar.
nchar and nvarchar will take up twice as much storage spac...
How can I multiply and divide using only bit shifting and adding?
...kes a constant multiple of time compared to addition and shifting. If I recall correctly, modern processors, if pipelined properly, can do multiplication just about as fast as addition, by messing with the utilization of the ALUs (arithmetic units) in the processor.
...
How can I hash a password in Java?
...
You can actually use a facility built in to the Java runtime to do this. The SunJCE in Java 6 supports PBKDF2, which is a good algorithm to use for password hashing.
byte[] salt = new byte[16];
random.nextBytes(salt);
KeySpec spec = new...
How can I setup & run PhantomJS on Ubuntu?
... to add one additional symlink to /usr/bin/, and I did direct symlinks for all 3 - see below.
I'm installing on Ubuntu server Natty Narwhal.
This is exactly what I did.
cd /usr/local/share
sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf ...
Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...
C++ display stack trace on exception
...re details.
On MSVC then you can use the StackWalker library that handles all of the underlying API calls needed for Windows.
You'll have to figure out the best way to integrate this functionality into your app, but the amount of code you need to write should be minimal.
...
Java Desktop application: SWT vs. Swing [closed]
...ava library, no need for
additional native libraries
works the same way on all platforms
Integrated GUI Editor in Netbeans and Eclipse
good online tutorials by Sun/Oracle
Supported by official java extensions (like java OpenGL)
Cons Swing:
Native look and feel may behave
different from the real...
How to convert a Title to a URL slug in jQuery?
...on an app in CodeIgniter, and I am trying to make a field on a form dynamically generate the URL slug. What I'd like to do is remove the punctuation, convert it to lowercase, and replace the spaces with hyphens. So for example, Shane's Rib Shack would become shanes-rib-shack.
...
How to wait for a BackgroundWorker to cancel?
...Async();
_resetEvent.WaitOne(); // will block until _resetEvent.Set() call made
}
void worker_DoWork(object sender, DoWorkEventArgs e)
{
while(!e.Cancel)
{
// do something
}
_resetEvent.Set(); // signal that worker is done
}
...
Can anyone explain python's relative imports?
...
Thanks, but this honestly seems really silly. For such a beautiful language, I can't believe the designers would create such a restriction. Isn't there any other way?
– carl
Dec 16 '09 at 23:48
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