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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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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 do I find out which DOM element has the focus?
...ript, which element currently has focus. I've been looking through the DOM and haven't found what I need, yet. Is there a way to do this, and how?
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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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CURL alternative in Python
...r.add_password(None, 'https://app.streamsend.com/emails', 'login', 'key')
handler = urllib2.HTTPBasicAuthHandler(manager)
director = urllib2.OpenerDirector()
director.add_handler(handler)
req = urllib2.Request('https://app.streamsend.com/emails', headers = {'Accept' : 'application/xml'})
result =...
Is “else if” a single keyword?
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They are not a single keyword if we go to the draft C++ standard section 2.12 Keywords table 4 lists both if and else separately and there is no else if keyword. We can find a more accessible list of C++ keywords by going to cppreferences section on keywords.
The grammar in sectio...
Formatting code in Notepad++
...shortcut to format code in Notepad++ ?
I'm mainly working with HTML, CSS and Python code.
12 Answers
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What is the difference between `raise “foo”` and `raise Exception.new(“foo”)`?
...echnically, the first raises a RuntimeError with the message set to "foo", and the second raises an Exception with the message set to "foo".
Practically, there is a significant difference between when you would want to use the former and when you want to use the latter.
Simply put, you probably w...
Why should I use core.autocrlf=true in Git?
I have a Git repository that is accessed from both Windows and OS X, and that I know already contains some files with CRLF line-endings. As far as I can tell, there are two ways to deal with this:
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