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E11000 duplicate key error index in mongodb mongoose
Following is my user schema in user.js model -
25 Answers
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How to get error message when ifstream open fails
...lying functions may not set errno at all (direct system calls on Linux, or Win32). This doesn't work on many real world implementations.
– strcat
Mar 12 '14 at 6:40
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原子vector的一种实现源码(atomic-vector) - C/C++ - 清泛网 - 专注C/C++及内核技术
...接
源码依赖Facebook的folly库，稍加适配改成了独立运行的版本，代码比较简单，实现分配好空间，然后对元素进行原子交换，扩容采用链表的形式，代码可直接运行。
测试代码：
HPHP::AtomicVector<float> v_atom(2, 0.f);
void atom_vecto...
How do I find out which process is locking a file using .NET?
...as impossible to reliably get the list of processes locking a file because Windows simply did not track that information. To support the Restart Manager API, that information is now tracked.
I put together code that takes the path of a file and returns a List<Process> of all processes that a...
What is the difference between include and extend in Ruby?
...ils about include, with its default behavior, assuming you've run the following code
class Klazz
include Mod
end
If Mod is already included in Klazz, or one of its ancestors, the include statement has no effect
It also includes Mod's constants in Klazz, as long as they don't clash
It gives Kla...
String concatenation: concat() vs “+” operator
...thod should be faster. However, with more strings the StringBuilder method wins, at least in terms of performance.
The source code of String and StringBuilder (and its package-private base class) is available in src.zip of the Sun JDK. You can see that you are building up a char array (resizing as ...
Join vs. sub-query
...version-specific and query-specific.
Historically, explicit joins usually win, hence the established wisdom that joins are better, but optimisers are getting better all the time, and so I prefer to write queries first in a logically coherent way, and then restructure if performance constraints warr...
Does pandas iterrows have performance issues?
...ly at the start of the iteration; this savings alone is one of the biggest wins.
Better caching: Iterating over a C array is cache-friendly and thus very fast. A pandas DataFrame is a "column-oriented table", which means that each column is really just an array. So the native actions you can perform...
乘着App的创业浪潮 行业短信也迎来了新生和爆发 - 资讯 - 清泛网 - 专注C/C...
...网以及O2O、P2P、APP爆发的浪潮迎来了新生。
新生之后，如何提升用户体验，解决消息延迟、被拦截等问题成为了行业短信面临的最大难题。
逆势崛起：验证短信迎来脱胎换骨
毫无疑问，短信正在死亡，最具有代表性的便是拜...
How to get time in milliseconds since the unix epoch in Javascript? [duplicate]
...amp in milliseconds
console.log( now );
Prior to ECMAScript5 (I.E. Internet Explorer 8 and older) you needed to construct a Date object, from which there are several ways to get a unix timestamp in milliseconds:
console.log( +new Date );
console.log( (new Date).getTime() );
console.lo...