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Nullable Foreign Key bad practice?
... read.
Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...
How do I shuffle an array in Swift?
...Distance` in < Swift 4.1
let d: Int = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
let i = index(firstUnshuffled, offsetBy: d)
swapAt(firstUnshuffled, i)
}
}
}
extension Sequence {
/// Returns an array with the contents of this...
Can I list-initialize a vector of move-only type?
...nitializer list elements in the current revision of the language.
Specifically, we have:
typedef const E& reference;
typedef const E& const_reference;
typedef const E* iterator;
typedef const E* const_iterator;
const E* begin() const noexcept; // first element
const E* end() const noexce...
How to draw a line in android
...rself just simple and clean add the line in xml.
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@android:color/black" />
The example code I provided will generate a line that fills the screen in width and has a height of one dp.
If you have ...
is_file or file_exists in PHP
I need to check if a file is on HDD at a specified location ($path.$file_name).
5 Answers
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OceanBase使用libeasy原理源码分析：客户端 - 数据库(内核) - 清泛网 - 专...
...端》，作为客户端使用时，会涉及到一些数据结构，easy_session_t, easy_client_t, easy_hash_t, easy_hash_list_t等。
easy_session_t用来封装一个要发出去的请求，easy_client_t用来封装一个TCP连接的发起端，easy_hash_t是一个哈希表，easy_hash_list_t是...
user authentication libraries for node.js?
...
Among all auth packages for node I selected passport. It's well-documented and easy to use, and supports more strategies.
– tech-man
May 14 '12 at 4:16
...
Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...ith something like map or collect would be built in, and nobody has to see all the hoops the compiler has to go through to make them work smoothly. In Scala, it's all in a library, and therefore out in the open.
In fact the functionality of map that's supported by its complicated type is pretty adv...
离线版启动超时，有报错日志 - App Inventor 2 离线版 - 清泛IT社区，为创新赋能！
...ources\app.asar.unpacked\OpenJDK\bin\java, --add-opens=java.base/java.lang=ALL-UNNAMED, -Xmx4G, --add-opens, java.base/java.net=ALL-UNNAMED, --add-opens, java.base/sun.net.www.protocol.http=ALL-UNNAMED, --add-opens, java.base/sun.net.www.protocol.https=ALL-UNNAMED, -Dfile.encoding=UTF-8, -classpath,...
How to loop over files in directory and change path and add suffix to filename
...le of notes first: when you use Data/data1.txt as an argument, should it really be /Data/data1.txt (with a leading slash)? Also, should the outer loop scan only for .txt files, or all files in /Data? Here's an answer, assuming /Data/data1.txt and .txt files only:
#!/bin/bash
for filename in /Data/*...