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JPA OneToMany not deleting child
I have a problem with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when I remove them from the collection.
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Should I put #! (shebang) in Python scripts, and what form should it take?
...line in any script determines the script's ability to be executed like a standalone executable without typing python beforehand in the terminal or when double clicking it in a file manager (when configured properly). It isn't necessary but generally put there so when someone sees the file opened in ...
sys.argv[1] meaning in script
I'm currently teaching myself Python and was just wondering (In reference to my example below) in simplified terms what the sys.argv[1] represents. Is it simply asking for an input?
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Calling C++ class methods via a function pointer
How do I obtain a function pointer for a class member function, and later call that member function with a specific object? I’d like to write:
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Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
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Using git, how do I ignore a file in one branch but have it committed in another branch?
...certain, patched versions of git. See a new answer pointing to workarounds and another answer and subsequent comments for a hint which versions may work.
I wrote a blog post on how to effectively use the excludesfile for different branches, like one for public github and one for heroku deployment....
Eclipse - no Java (JRE) / (JDK) … no virtual machine
... copying it from another computer: there is no special installation steps, and you can have as many different JVM versions (1.4, 5.0, 6.0...) as you want, "installed" (copied) almost anywhere on your disk.
I would recommend to always run Eclipse with the lastest JRE possible (to benefit from the lat...
R memory management / cannot allocate vector of size n Mb
...e Matrix package for e.g.) for sparse matrices.
Keep all other processes and objects in R to a minimum when you need to make objects of this size. Use gc() to clear now unused memory, or, better only create the object you need in one session.
If the above cannot help, get a 64-bit machine with a...
Haskell offline documentation?
...ossibilities, if any, for getting offline docs for Haskell core libraries (and maybe more)?
9 Answers
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How does UTF-8 “variable-width encoding” work?
The unicode standard has enough code-points in it that you need 4 bytes to store them all. That's what the UTF-32 encoding does. Yet the UTF-8 encoding somehow squeezes these into much smaller spaces by using something called "variable-width encoding".
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