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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...
Is there a standard sign function (signum, sgn) in C/C++?
...ive numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
...
Return HTTP status code 201 in flask
...
You can read about it here.
return render_template('page.html'), 201
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Setting a system environment variable from a Windows batch file?
...
Simple example for how to set JAVA_HOME with setx.exe in command line:
setx JAVA_HOME "C:\Program Files (x86)\Java\jdk1.7.0_04"
This will set environment variable "JAVA_HOME" for current user. If you want to set a variable for all users, you have to use op...
How do you use gcc to generate assembly code in Intel syntax?
.... See LLVM Bug 24232: [X86] Inline assembly operands don't work with .intel_syntax. Also, Clang ignores prefix/noprefix (not sure if it matters if Clang consumes the assembly).
– jww
Sep 26 '15 at 22:34
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How to implement a property in an interface
...ic string Name { get; set; }
}
class Company : IName
{
private string _company { get; set; }
public string Name
{
get
{
return _company;
}
set
{
_company = value;
}
}
}
class Client
{
static void Main(st...
How to take screenshot of a div with JavaScript?
...
When the quiz is finished, do this:
var c = document.getElementById('the_canvas_element_id');
var t = c.getContext('2d');
/* then use the canvas 2D drawing functions to add text, etc. for the result */
When the user clicks "Capture", do this:
window.open('', document.getElementById('the_canvas...
TimeStamp on file name using PowerShell
...g from the output of Get-ChildItem:
Get-ChildItem *.zip | Foreach {
"$($_.DirectoryName)\$($_.BaseName) $(get-date -f yyyy-MM-dd)$($_.extension)"}
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Understanding NSRunLoop
.../Conceptual/Multithreading/RunLoopManagement/RunLoopManagement.html#//apple_ref/doc/uid/10000057i-CH16-SW1
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How do I show a Save As dialog in WPF?
...w : System.Windows.Forms.IWin32Window
{
private readonly System.IntPtr _handle;
public OldWindow(System.IntPtr handle)
{
_handle = handle;
}
System.IntPtr System.Windows.Forms.IWin32Window.Handle
{
get { return _handle; }
}
}
#endregion
Capitalize() is ...