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What is a columnar database?
...an easy fashion).
How do they differ from relational databases?
They generally differ from traditional (row-oriented) databases with regards to ...
performance...
storage requirements ...
ease of modification of the schema ...
...in specific use cases of DBMSes.
In particular they offer advanta...
What do (lambda) function closures capture?
...the name and scope of the variable, not the object it's pointing to. Since all the functions in your example are created in the same scope and use the same variable name, they always refer to the same variable.
EDIT: Regarding your other question of how to overcome this, there are two ways that com...
Creating a blocking Queue in .NET?
...threads reading from the same queue. If the queue reaches a specific size all threads that are filling the queue will be blocked on add until an item is removed from the queue.
...
static constructors in C++? I need to initialize private static objects
... to have a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables ...
Why would $_FILES be empty when uploading files to PHP?
I have WampServer 2 installed on my Windows 7 computer. I'm using Apache 2.2.11 and PHP 5.2.11. When I attempt to upload any file from a form, it seems to upload, but in PHP, the $_FILES array is empty. There is no file in the c:\wamp\tmp folder. I have configured php.ini to allow file uploads...
What is the copy-and-swap idiom?
...s arguably the most nuanced and difficult. How should it be done? What pitfalls need to be avoided?
The copy-and-swap idiom is the solution, and elegantly assists the assignment operator in achieving two things: avoiding code duplication, and providing a strong exception guarantee.
How does it wor...
Get the device width in javascript
...th property.
Sometimes it's also useful to use window.innerWidth (not typically found on mobile devices) instead of screen width when dealing with desktop browsers where the window size is often less than the device screen size.
Typically, when dealing with mobile devices AND desktop browsers I use...
Print current call stack from a method in Python code
In Python, how can I print the current call stack from within a method (for debugging purposes).
7 Answers
...
Reminder - \r\n or \n\r?
...Mac keyboards, or else you might later look at a PC keyboard, see the key called "Enter," and get the letter order wrong!
– Rob Kennedy
Jun 30 '11 at 19:36
3
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C++ 读写xml方法整理（持续更新） - C/C++ - 清泛网 - 专注C/C++及内核技术
...*******************
* outline.c
*
* Copyright 1999, Clark Cooper
* All rights reserved.
*/
#include <stdio.h>
#include <expat.h>
#if defined(__amigaos__) && defined(__USE_INLINE__)
#include <proto/expat.h>
#endif
#ifdef XML_LARGE_SIZE
#if defined(XML_USE_MSC_EXTENSIONS) && _MS...