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Get ID of last inserted document in a mongoDB w/ Java driver
...h MongoDB plainly auto-generates ObjectId's. However, your solution of manually creating an ObjectId does work, and thanks for this option!
– Apophenia Overload
Dec 4 '12 at 8:39
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What does [:] mean?
...he type of population. If population is a list, this line will create a shallow copy of the list. For an object of type tuple or a str, it will do nothing (the line will do the same without [:]), and for a (say) NumPy array, it will create a new view to the same data.
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How to determine whether code is running in DEBUG / RELEASE build?
...EBUG changed to another variable name such as DEBUG_MODE.
then conditionally code for DEBUG in your source files
#ifdef DEBUG
// Something to log your sensitive data here
#else
//
#endif
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Is gcc's __attribute__((packed)) / #pragma pack unsafe?
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Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardwa...
Can I use multiple versions of jQuery on the same page?
...trol. Can I safely just use the latter half, or do both libraries need to call noConflict()?
– Bungle
Oct 14 '09 at 15:05
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Can I have multiple Xcode versions installed?
Is it possible to have more than one version of Xcode installed at the same time?
12 Answers
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Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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What does the PHP error message “Notice: Use of undefined constant” mean?
...l_escape_string($_POST['message']);
As is, it was looking for constants called department, name, email, message, etc. When it doesn't find such a constant, PHP (bizarrely) interprets it as a string ('department', etc). Obviously, this can easily break if you do defined such a constant later (tho...
General guidelines to avoid memory leaks in C++ [closed]
... programs? How do I figure out who should free memory that has been dynamically allocated?
29 Answers
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Rails :include vs. :joins
...de functionality was changed with Rails 2.1. Rails used to do the join in all cases, but for performance reasons it was changed to use multiple queries in some circumstances. This blog post by Fabio Akita has some good information on the change (see the section entitled "Optimized Eager Loading")....