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#1071 - Specified key was too long; max key length is 1000 bytes
...per column as you define the index. For example:
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KEY `index` (`parent_menu_id`,`menu_link`(50),`plugin`(50),`alias`(50))
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But what's the best prefix length for a given column? Here's a method to find out:
SELECT
ROUND(SUM(LENGTH(`menu_link`)<10)*100/COUNT(`menu_link`),2) AS pct_leng...
Create subdomains on the fly with .htaccess (PHP)
...P
Then in your PHP scripts you can find out the domain by looking in the $_SERVER super global variable. Here is an example of grabbing the subdomain in PHP:
preg_match('/([^.]+)\.example\.org/', $_SERVER['SERVER_NAME'], $matches);
if(isset($matches[1])) {
$subdomain = $matches[1];
}
I have ...
Automatically import modules when entering the python or ipython interpreter
...roduction scripts.
For Ipython, see this tutorial on how to make a ipython_config file
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Sleep for milliseconds
... facilities:
#include <chrono>
#include <thread>
std::this_thread::sleep_for(std::chrono::milliseconds(x));
Clear and readable, no more need to guess at what units the sleep() function takes.
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How to loop backwards in python? [duplicate]
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for x in reversed(whatever):
do_something()
This works on basically everything that has a defined order, including xrange objects and lists.
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How do you split a list into evenly sized chunks?
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@Nhoj_Gonk Oops it's not an infinite loop, but chunks(L, 0) would raise a ValueError without the max(). Instead, the max() turns anything less than 1 into a 1.
– Bob Stein
Apr 27 at 9:58
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maximum value of int
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In C++:
#include <limits>
then use
int imin = std::numeric_limits<int>::min(); // minimum value
int imax = std::numeric_limits<int>::max();
std::numeric_limits is a template type which can be instantiated with other types:
float fmin = std::numeric_limits<float>...
C++中智能指针的设计和使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...释放对象拥有权限、引用计数等，控制权转移等）。auto_ptr 即是一种常见的智能指针。
智能指针通常用类模板实现：
template <class T>
class smartpointer
{
private:
T *_ptr;
public:
smartpointer(T *p) : _ptr(p) //构造函数
{
}
T& oper...
获取文件系统映像及恢复删除的数据（FAT文件系统格式描述） - C/C++ - 清泛...
...有几个。下面的代码执行了这个任务：
RemovableDeviceInfo_vt Functions::SearchRemovalDisks()
{
RemovableDeviceInfo_vt devInfos; //result
/*GUID_DEVCLASS_DISKDRIVE*/
CONST CLSID CLSID_DeviceInstance = { 0x4D36E967, 0xE325, 0x11CE, { 0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe...
How to get the width and height of an android.widget.ImageView?
...eight, finalWidth;
final ImageView iv = (ImageView)findViewById(R.id.scaled_image);
final TextView tv = (TextView)findViewById(R.id.size_label);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
...