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Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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When to use pip requirements file versus install_requires in setup.py?
I'm using pip with virtualenv to package and install some Python libraries.
4 Answers
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How to port data-only volumes from one host to another?
As described in the Docker documentation on Working with Volumes there is the concept of so-called data-only containers, which provide a volume that can be mounted into multiple other containers, no matter whether the data-only container is actually running or not.
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log4j logging hierarchy order
What is the hierarchy of log4j logging?
6 Answers
6
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What is the difference between lock and Mutex?
What is the difference between lock and Mutex? Why can't they be used interchangeably?
7 Answers
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Need to understand the usage of SemaphoreSlim
Here is the code I have but I don't understand what SemaphoreSlim is doing.
3 Answers
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Is the VC++ code DOM accessible from VS addons?
Visual Studio IntelliSense for VC++ includes the "complete" EDG C++ parser (also used by Intel and others). Since the C# Code DOM is accessible to addons (correct me if I'm wrong), is the C++ Code DOM also accessible? Can this be used to analyse an open VC++ project within the VS environment?
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std::string的截取字符串的方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
....0.1:8888");
int index = ip.find_last_of(':');
//ip
ip.substr(0, index).c_str();
//port
ip.substr(index + 1).c_str();
int find_first_of(char c, int start = 0):
查找字符串中第1个出现的c,由位置start开始。 如果有匹配，则返回匹配位置；否则，返回-1.默认情...
How to install a node.js module without using npm?
There are quite a few modules which are listed on node's github page but are not published with the npm-registry. These modules can't be installed using npm.
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Understanding Fragment's setRetainInstance(boolean)
Starting with the documentation:
5 Answers
5
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