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Are GUID collisions possible?
I'm working on a database in SQL Server 2000 that uses a GUID for each user that uses the app it's tied to. Somehow, two users ended up with the same GUID. I know that microsoft uses an algorithm to generate a random GUID that has an extremely low chance of causing collisons, but is a collision stil...
Moving average or running mean
...msum[:-N]) / float(N)
The code to check
In[3]: x = numpy.random.random(100000)
In[4]: N = 1000
In[5]: %timeit result1 = numpy.convolve(x, numpy.ones((N,))/N, mode='valid')
10 loops, best of 3: 41.4 ms per loop
In[6]: %timeit result2 = running_mean(x, N)
1000 loops, best of 3: 1.04 ms per loop
N...
Identity increment is jumping in SQL Server database
...provement since SQL Server 2012.
It now by default uses a cache size of 1,000 when allocating IDENTITY values for an int column and restarting the service can "lose" unused values (The cache size is 10,000 for bigint/numeric).
This is mentioned in the documentation
SQL Server might cache iden...
Get hours difference between two dates in Moment Js
...time in nice human readable form, like this:
moment('2019-04-30T07:30:53.000Z').fromNow() // an hour ago || a day ago || 10 days ago
Or if you want that between two specific dates you can use:
var a = moment([2007, 0, 28]);
var b = moment([2007, 0, 29]);
a.from(b); // "a day ago"
Taken from ...
How to count string occurrence in string?
...is 25 chars length. with 2 occurences of the character 'o'. I
executed 1 000 000 times in Safari.
Safari 5.1
Benchmark> Total time execution: 5617 ms (regexp)
Benchmark> Total time execution: 881 ms (my function 6.4x faster)
Firefox 4
Benchmark> Total time execut...
Hash and salt passwords in C#
...
* Version 3:
* PBKDF2 with HMAC-SHA256, 128-bit salt, 256-bit subkey, 10000 iterations.
* Format: { 0x01, prf (UInt32), iter count (UInt32), salt length (UInt32), salt, subkey }
* (All UInt32s are stored big-endian.)
*/
public string HashPassword(string password)
{
var prf = KeyDerivatio...
How do I format a number with commas in T-SQL?
...onstrates adding commas:
PRINT FORMATMESSAGE('The number is: %s', format(5000000, '#,##0'))
-- Output
The number is: 5,000,000
Demo 2
Demonstrates commas and decimal points. Observe that it rounds the last digit if necessary.
PRINT FORMATMESSAGE('The number is: %s', format(5000000.759145678, '#...
Is it possible to apply CSS to half of a character?
...r-events: none; /* so the base char is selectable by mouse */
color: #000; /* for demo purposes */
text-shadow: 2px 2px 0px #0af; /* for demo purposes */
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<p>Single Characters:&l...
Natural Sort Order in C#
...
Great answer. Caveat: This won't work with Win2000, for those few folks still running things on that operating system. On the other hand, there's enough hints between Kaplan's blog and the MSDN documentation to create a similar function.
– Chris Char...
Random number from a range in a Bash Script
I need to generate a random port number between 2000-65000 from a shell script. The problem is $RANDOM is a 15-bit number, so I'm stuck!
...