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NOT IN vs NOT EXISTS
...be the same at the moment but if either column is altered in the future to allow NULLs the NOT IN version will need to do more work (even if no NULLs are actually present in the data) and the semantics of NOT IN if NULLs are present are unlikely to be the ones you want anyway.
When neither Products...
Test a weekly cron job [closed]
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This really shouldn't have been upvoted and accepted, beyond running the script it does nothing to tell you whether the script will actually work when run from cron. Use the excellent crontest script in one of the other answers to t...
Bytecode features not available in the Java language
...case of the invokespecial bytecode is handled for this class. It is set by all modern Java compilers (where "modern" is >= Java 1.1, if I remember correctly) and only ancient Java compilers produced class files where this was un-set. This flag exists only for backwards-compatibility reasons. Note...
Parsing JSON with Unix tools
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There are a number of tools specifically designed for the purpose of manipulating JSON from the command line, and will be a lot easier and more reliable than doing it with Awk, such as jq:
curl -s 'https://api.github.com/users/lambda' | jq -r '.name'
You can...
CA2202, how to solve this case
Can anybody tell me how to remove all CA2202 warnings from the following code?
12 Answers
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Protected in Interfaces
Why are all methods in an interface definition implicitly public ? Why does it not allow a protected method?
13 Answer...
What's the difference between .so, .la and .a library files?
...t in memory). But what is the difference between .a and .la ? Are these all static libraries?
1 Answer
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How to unzip a list of tuples into individual lists? [duplicate]
...l))
[(1, 3, 8), (2, 4, 9)]
The zip() function pairs up the elements from all inputs, starting with the first values, then the second, etc. By using *l you apply all tuples in l as separate arguments to the zip() function, so zip() pairs up 1 with 3 with 8 first, then 2 with 4 and 9. Those happen t...
Get the first item from an iterable that matches a condition
...ment against next (in that answer) is that you must handle an exception; really ?
– Abraham TS
Jan 24 '18 at 23:34
My ...
What's the difference between QMainWindow, QWidget and QDialog?
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A QWidget is the base class for all drawable classes in Qt. Any QWidget-based class can be shown as a window by showing it when it has no parent.
A QDialog is based on QWidget, but designed to be shown as a window. It will always appear in a window, and ...