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Django: Get an object form the DB, or 'None' if nothing matches
...get(*args, **kwargs)
except model.DoesNotExist:
return None
Call it like this
foo = get_or_none(Foo, baz=bar)
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Are there any Java method ordering conventions? [closed]
...er them in a sensible way. Is there a standard way of doing this? E.g. normally fields are listed before methods, the constructor(s) are listed before other methods, and getters/setters last; what about the remaining methods?
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MySQL order by before group by
...rect author and post is returned every time.
As a side note, while MySQL allows you to use an ORDER BY in a subquery and allows you to apply a GROUP BY to not every column in the SELECT list this behavior is not allowed in other databases including SQL Server.
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Shortest way to print current year in a website
...n the footer. I want to replace it with some JavaScript that will automatically update each year.
10 Answers
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img tag displays wrong orientation
... Why in the world do images even have orientation metadata? If you really wanted to rotate the picture then wouldn't you just shift around the pixels and swap the width for the height?
– Jack Giffin
Oct 29 '17 at 1:02
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What part of Hindley-Milner do you not understand?
...re are multiple expressions in [above], then consider them anded together; all of the [above] must be true in order to guarantee the [below].
: means has type
∈ means is in. (Likewise ∉ means "is not in".)
Γ is usually used to refer to an environment or context; in this case it can be thought o...
JPA eager fetch does not join
...ence between eager and lazy. In both cases JPA/Hibernate does not automatically join many-to-one relationships.
8 Answers
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What is aspect-oriented programming?
.... People seem to talk about aspect-oriented programming, but I've never really learned what it is or how to use it. What is the basic paradigm?
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How to prevent a dialog from closing when a button is clicked
...log. Every time no matter what the input is, the dialog should be automatically closed when I click on the "no" button. How can I disable this? By the way, I have used PositiveButton and NegativeButton for the button on dialog.
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Java 32-bit vs 64-bit compatibility
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I accidentally ran our (largeish) application on a 64bit VM rather than a 32bit VM and didn't notice until some external libraries (called by JNI) started failing.
Data serialized on a 32bit platform was read in on the 64bit platform ...