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count(*) vs count(column-name) - which is more correct? [duplicate]
... difference is:
COUNT(*) will count the number of records.
COUNT(column_name) will count the number of records where column_name is not null.
Therefore COUNT(*) is what you should use. If you're using MyISAM and there is no WHERE clause, then the optimiser doesn't even have to look at the tabl...
Ioc/DI - Why do I have to reference all layers/assemblies in application's entry point?
...ic class DependencyRegistrarModule : IHttpModule
{
private static bool _dependenciesRegistered;
private static readonly object Lock = new object();
public void Init(HttpApplication context)
{
context.BeginRequest += (sender, args) => EnsureDependenciesRegistered();
}
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How to get subarray from array?
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What K_7 said; most especially, monkey-patching the Builtins (Object, Array, Promise, etc) is very naughty. See the famous example of MooTools forcing a rename of the proposed native Array.prototype.contains to Array.prototype.incl...
What is the difference between map and flatMap and a good use case for each?
...th N.
For example, it maps from two lines into two line-lengths:
rdd.map(_.length).collect
res1: Array[Int] = Array(13, 16)
But flatMap (loosely speaking) transforms an RDD of length N into a collection of N collections, then flattens these into a single RDD of results.
rdd.flatMap(_.spli...
PHP random string generator
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All that work, why not just something like substr(str_shuffle(MD5(microtime())), 0, 10);?
– SpYk3HH
Apr 9 '14 at 13:06
5
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What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?
...g=-d -v release install
[signjar] Executing 'C:\Program Files\Java\jdk1.7.0_03\bin\jarsigner.exe' with arguments:
[signjar] '-keystore'
[signjar] 'C:\cygwin\home\Chloe\pairfinder\release.keystore'
[signjar] '-signedjar'
[signjar] 'C:\cygwin\home\Chloe\pairfinder\bin\PairFinder-release-unaligned.apk'...
ZeroMQ的学习和研究（PHP代码实例） - C/C++ - 清泛网 - 专注C/C++及内核技术
...ocket to talk to clients
$responder = new ZMQSocket ($context, ZMQ::SOCKET_REP);
$responder->bind ("tcp://*:5555");
while(true) {
// Wait for next request from client
$request = $responder->recv ();
printf ("Received request: [%s]\n", $request);
// Do some 'work'
sleep (1);
// Send re...
Generate MD5 hash string with T-SQL
...here a way to generate MD5 Hash string of type varchar(32) without using fn_varbintohexstr
9 Answers
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Understand convertRect:toView:, convertRect:FromView:, convertPoint:toView: and convertPoint:fromVie
... here I want to take some subview and put it in my view's coordinate space
_originalFrame = [[aView superview] convertRect: aView.frame toView: self];
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Return HTTP status code 201 in flask
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You can read about it here.
return render_template('page.html'), 201
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