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What's wrong with nullable columns in composite primary keys?
...key creation. If this was just a retrieval problem, you could use where pk_1 = 'a' and pk_2 = 'b' with normal values, and switch to where pk_1 is null and pk_2 = 'b' when there are nulls.
– EoghanM
Mar 15 '13 at 9:59
...
How do I write LINQ's .Skip(1000).Take(100) in pure SQL?
...
In SQL Server 2005 and above you can use ROW_NUMBER function. eg.
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrd...
Windows下 C++网络延时检测 - C/C++ - 清泛网 - 专注C/C++及内核技术
...现的呢？直接上代码吧，亲测可用：
Ping.h
#ifndef CPING_H
#define CPING_H
#include <windows.h>
#include <conio.h>
#include <winnt.h>
#define PING_TIMES 2 //ping 4 次
typedef struct _IPINFO
{
unsigned char Ttl; // Time To Live
unsigned char Tos; // Type Of Se...
Python concatenate text files
...path/to/output/file', 'w') as outfile:
for line in itertools.chain.from_iterable(itertools.imap(open, filnames)):
outfile.write(line)
Sadly, this last method leaves a few open file descriptors, which the GC should take care of anyway. I just thought it was interesting
...
How to read last commit comment?
...t was what I needed to not have the commit message indented. And yes, @Juh_, even though git gui doesn't linewrap for you, it's a good idea to use 80column text in commit messages, not line-per-paragraph.
– Peter Cordes
Dec 13 '14 at 1:06
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Why are dates calculated from January 1st, 1970?
...
Astronomers use their own epochal date: http://en.wikipedia.org/wiki/Epoch_(astronomy)
Why? A date has to be chosen to make the math work out. Any random date will work.
A date far in the past avoids negative numbers for the general case.
Some of the smarter packages use the proleptic Gregoria...
How do I get the entity that represents the current user in Symfony2?
...*
* @var Security
*/
private $security;
public function __construct(Security $security)
{
$this->security = $security;
}
public function privatePage() : Response
{
$user = $this->security->getUser(); // null or UserInterface, if logged in
...
How does Apple know you are using private API?
...ist all linked symbols. This can detect
Undocumented C functions such as _UIImageWithName;
Objective-C classes such as UIProgressHUD
Ivars such as UITouch._phase (which could be the cause of rejection of Three20-based apps last few months.)
3. Listing Objective-C selectors, or strings
Objective...
How do I speed up the gwt compiler?
...ur gwt.xml:
<define-property name="user.agent" values="ie6,gecko,gecko1_8"></define-property>
or in gwt 2.x syntax, and for one browser only:
<set-property name="user.agent" value="gecko1_8"/>
This, for example, will compile your application for IE and FF only. If you know yo...
How can I clone an SQL Server database on the same server in SQL Server 2008 Express?
...
Version 2012
Click download button and check ENU\x64\SQLManagementStudio_x64_ENU.exe
Version 2014
Click download button and check MgmtStudio 64BIT\SQLManagementStudio_x64_ENU.exe
Open Microsoft SQL Management Studio.
Backup original database to .BAK file (db -> Task -> Backup).
Create em...