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Unique constraint on multiple columns
...ied from technet's documentation, is in the form of:
CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ]
(
column [ ASC | DESC ] [ ,...n ]
)
Therefore, the resuting table definition would be:
CREATE TABLE [dbo].[user](
[userID] [int] IDENTITY(1,1) NOT NULL,
[fcode] [int] ...
How to write log base(2) in c/c++
...
#define M_LOG2E 1.44269504088896340736 // log2(e)
inline long double log2(const long double x){
return log(x) * M_LOG2E;
}
(multiplication may be faster than division)
...
Redirecting from HTTP to HTTPS with PHP
...
Try something like this (should work for Apache and IIS):
if (empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] === "off") {
$location = 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
header('HTTP/1.1 301 Moved Permanently');
header('Location: ' . $location);
exit;
}...
Cloning an Object in Node.js
...ion is now marked as deprecated in the documentation of Node.js:
The util._extend() method was never intended to be used outside of internal Node.js modules. The community found and used it anyway.
It is deprecated and should not be used in new code. JavaScript comes with very similar built-in func...
How do I add a placeholder on a CharField in Django?
...t specify the field (e.g. for some dynamic method), you can use this:
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwargs)
self.fields['email'].widget.attrs['placeholder'] = self.fields['email'].label or 'email@address.nl'
It also allows the placeholder to de...
What are some uses of decltype(auto)?
...p;&
auto x6a = { 1, 2 }; // decltype(x6a) is std::initializer_list<int>
decltype(auto) x6d = { 1, 2 }; // error, { 1, 2 } is not an expression
auto *x7a = &i; // decltype(x7a) is int*
decltype(auto)*x7d = &i; // error, declared type is not plain declt...
In PHP, can you instantiate an object and call a method on the same line?
...So, if you declared a class like this :
class Test {
public function __construct($param) {
$this->_var = $param;
}
public function myMethod() {
return $this->_var * 2;
}
protected $_var;
}
You can then declare a function that returns an instance of that ...
What can you do in MSIL that you cannot do in C# or VB.NET? [closed]
...etty much all over the place. Examine the IL for this: "let print x = print_any x".
– MichaelGG
Feb 24 '09 at 23:22
1
...
Multiprocessing vs Threading Python [duplicate]
...n3
import multiprocessing
import threading
import time
import sys
def cpu_func(result, niters):
'''
A useless CPU bound function.
'''
for i in range(niters):
result = (result * result * i + 2 * result * i * i + 3) % 10000000
return result
class CpuThread(threading.Thre...
Is there a performance difference between i++ and ++i in C++?
... this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) // called for i++
{
Foo tmp(*this); // variable "tmp" cannot be optimized away by the compiler
++(*this);
return tmp;
}
Since the compiler isn't generating code, but just calling an operator++ ...