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What is PostgreSQL explain telling me exactly?
...content: "• EXPLAIN works on any DML not just SELECT (ie UPDATE, DELETE, and INSERT)". My biggest misunderstanding is what "startup" time means, and that's not explained anywhere in these ~30 slides.
– Mark E. Haase
Feb 19 '16 at 15:51
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Why is NaN not equal to NaN? [duplicate]
The relevant IEEE standard defines a numeric constant NaN (not a number) and prescribes that NaN should compare as not equal to itself. Why is that?
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How to get current memory usage in android?
I have used /proc/meminfo and parsed command response.however it result shows that :
11 Answers
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How to map atan2() to degrees 0-360
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For those not comfortable with this notation, and without the conversion to degrees built in: if(x>0) {radians = x;} else {radians = 2*PI + x;} so we are just adding 2PI to the result if it is less than 0.
– David Doria
Sep 25 '1...
What requests do browsers' “F5” and “Ctrl + F5” refreshes generate?
Is there a standard for what actions F5 and Ctrl + F5 trigger in web browsers?
6 Answers
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What's wrong with nullable columns in composite primary keys?
...keys is not clean relational database design.
If there are two entities A and B where A can optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it would contain a record, if there isn't then i...
Run an untrusted C program in a sandbox in Linux that prevents it from opening files, forking, etc.?
...was wondering if there exists a way to run an untrusted C program under a sandbox in Linux. Something that would prevent the program from opening files, or network connections, or forking, exec, etc?
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How to re import an updated package while in Python Interpreter? [duplicate]
I often test my module in the Python Interpreter, and when I see an error, I quickly update the .py file. But how do I make it reflect on the Interpreter ? So, far I have been exiting and reentering the Interpreter because re importing the file again is not working for me.
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What's the difference between getRequestURI and getPathInfo methods in HttpServletRequest?
... lightweight front-controller. I need to match request paths to different handlers (actions) in order to choose the correct one.
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Can not connect to local PostgreSQL
...really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to access the socket file. To confirm this I've done some tests on Ubuntu and p...