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Why does NULL = NULL evaluate to false in SQL server
... in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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What is “thread local storage” in Python, and why do I need it?
...on-local variables (because each function call gets its own set of locals, and threads are always separate function calls.) And even then, only the variables themselves (the names that refer to objects) are local to the function; objects themselves are always global, and anything can refer to them.
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How to get the process ID to kill a nohup process?
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When using nohup and you put the task in the background, the background operator (&) will give you the PID at the command prompt. If your plan is to manually manage the process, you can save that PID and use it later to kill the process i...
What does character set and collation mean exactly?
I can read the MySQL documentation and it's pretty clear. But, how does one decide which character set to use? On what data does collation have an effect?
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Greenlet Vs. Threads
I am new to gevents and greenlets. I found some good documentation on how to work with them, but none gave me justification on how and when I should use greenlets!
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How to paste yanked text into the Vim command line
I'd like to paste yanked text into Vim's command line. Is it possible?
10 Answers
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Difference between an application server and a servlet container?
I am trying to understand the difference between a full fledged application server (e.g. Weblogic, JBoss etc.) and a servlet container (Tomcat, Jetty etc.).
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How to install Java SDK on CentOS?
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The following command will return a list of all packages directly related to Java. They will be in the format of java-<version>.
$ yum search java | grep 'java-'
If there are no available packages, then you may need to download a new ...
How do you use “
I just finished reading about scoping in the R intro , and am very curious about the <<- assignment.
6 Answers
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Visual Studio displaying errors even if projects build
I have a problem with Visual Studio on a C# solution. It displays totally random errors, but the projects build. Right now, I have 33 files with errors, and I can see red squiggly lines in all of them.
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