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Foreign key from one app into another in Django
...efine a foreign key in a models.py file in Django that is a reference to a table in another app?
3 Answers
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Proper way to make HTML nested list?
...e list — this is known as "nesting" a list. It is useful for things like tables of contents, such as the one at the start of this article:
Chapter One
Section One
Section Two
Section Three
Chapter Two
Chapter Three
The key to nesting lists is to remember that the nes...
What is a WeakHashMap and when to use it? [duplicate]
...or caches/lookup storage.
Weak reference are not restricted to these hash tables, you can use WeakReference for single objects. They are useful to save resource, you can keep a reference to something but allow it to be collected when nothing else references it. (BTW, a strong reference is a normal...
关于php的socket初探 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...塞的古老模型:属于同步阻塞 IO 模型,代码如下:
socket_server.php
<?php
/**
* SocketServer Class
* By James.Huang <shagoo#gmail.com>
**/
set_time_limit(0);
class SocketServer
{
private static $socket;
function SocketServer($port)
{ ...
Efficiency of purely functional programming
...out simulating random access memory using only pointers). Pippenger also establishes that there are algorithms for which that is the best you can do; there are problems which are O(n) in the impure system which are Ω(n log n) in the pure system.
There are a few caveats to be made about this paper....
Android Get Current timestamp?
...
From developers blog:
System.currentTimeMillis() is the standard "wall" clock (time and date) expressing milliseconds since the epoch. The wall clock can be set by the user or the phone network (see setCurrentTimeMillis(long)), so the time may jump backwards or forwards unpredictably. This c...
Why is sed not recognizing \t as a tab?
...
Not all versions of sed understand \t. Just insert a literal tab instead (press Ctrl-V then Tab).
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What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
...and()) {
command.CommandText = "SELECT MyColumn1, MyColumn2 FROM MyTable";
using (var reader = command.ExecuteReader()) {
while (reader.Read()) {
ProcessData(reader.GetString(2)); // Throws!
}
}
}
}
GetString() will throw IndexOu...
Two-way encryption: I need to store passwords that can be retrieved
...
Personally, I would use mcrypt like others posted. But there is much more to note...
How do I encrypt and decrypt a password in PHP?
See below for a strong class that takes care of everything for you:
What is the safest algorit...
Error handling with node.js streams
...ansform
Transform streams are both readable and writeable, and thus are really good 'middle' streams. For this reason, they are sometimes referred to as through streams. They are similar to a duplex stream in this way, except they provide a nice interface to manipulate the data rather than just sen...
