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Find MongoDB records where array field is not empty
All of my records have a field called "pictures". This field is an array of strings.
11 Answers
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Targeting .NET Framework 4.5 via Visual Studio 2010
Today I installed the .NET Framework 4.5 on my machine expecting to be able to use it from Visual Studio 2010, since it's just a minor update that should't pose problems for Visual Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies r...
select and update database record with a single queryset
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@learning well dude, it all depends on your scenario. The update method is great for mass updates, but it should set off a warning in your head when you use it that you need to review any signals attached to that object that might also need to be m...
To underscore or to not to underscore, that is the question
...other framework languages? For example since C# is case-sensitive you can call a field "foo" and the public property "Foo" and it works fine.
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How do I copy the contents of a String to the clipboard in C#? [duplicate]
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I wish calling SetText were that easy but there are quite a few gotchas that you have to deal with. You have to make sure that the thread you are calling it on is running in the STA. It can sometimes fail with an access denied error ...
How to create an object for a Django model with a many to many field?
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For future visitors, you can create an object and all of its m2m objects in 2 queries using the new bulk_create in django 1.4. Note that this is only usable if you don't require any pre or post-processing on the data with save() methods or signals. What you insert is exactly...
float64 with pandas to_csv
...mvent this problem, I recommend you create another CSV file which contains all figures as integers, for example multiplying by 100, 1000 or other factor which turns out to be convenient. Inside your application, read the CSV file as usual and you will get those integer figures back. Then convert tho...
STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...定义一个结构体来试试：[cpp]view plaincopystructa{char*pName;intm_a;} 引言
STL的map容器中，key的类型是不是随意的呢？
实践
编写测试代码
定义一个结构体来试试：
struct a
{
char* pName;
int m_a;
};
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map<a, int> mp;
a ...
PHP - Move a file into a different folder on the server
I need to allow users on my website to delete their images off the server after they have uploaded them if they no longer want them. I was previously using the unlink function in PHP but have since been told that this can be quite risky and a security issue. (Previous code below:)
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What is the JavaScript convention for no operation?
... "function" // returns true
It can be invoked as a function and essentially does nothing as shown here:
setTimeout(function() {
console.log('Start: ', Date.now());
Function.prototype();
console.log('End : ', Date.now());
}, 1000);
Although this is a "true noop" since...