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Django ManyToMany filter()
... User.objects.filter(zones__in=[<id1>])
# filtering on a few zones, by id
users_in_zones = User.objects.filter(zones__in=[<id1>, <id2>, <id3>])
# and by zone object (object gets converted to pk under the covers)
users_in_zones = User.objects.filter(zones__in=[zone1, zone2, z...
http HEAD vs GET performance
... or is slow to retrieve at the server, you might not see a measurable gain by using HEAD instead of GET. It could be that retrieving the meta data is not any faster than retrieving the entire resource.
You could implement both options and benchmark them to see which is faster, but rather than micro...
Setting Short Value Java
...
In Java, integer literals are of type int by default. For some other types, you may suffix the literal with a case-insensitive letter like L, D, F to specify a long, double, or float, respectively. Note it is common practice to use uppercase letters for better readab...
Mipmap drawables for icons
...ity. For example on an hdpi tablet the launcher might load the xhdpi icon. By placing your launcher icon in the mipmap-xhdpi directory, it will not be stripped the way a drawable-xhdpi directory is when building an APK for hdpi devices. If you're building a single APK for all devices, then this does...
What is the difference between encrypting and signing in asymmetric encryption?
... your public key itself, which you have earlier generated for free, signed by an authority which might or might not charge you money for that.
– Quassnoi
Jul 26 '19 at 10:45
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R script line numbers at error?
...l debugging suspects:
debug()
browser()
options(error=recover) [followed by options(error = NULL) to revert it]
You might want to look at this related post.
[Edit:] Sorry...just saw that you're running this from the command line. In that case I would suggest working with the options(error) fun...
UIPopovercontroller dealloc reached while popover is still visible
...en you don't need to keep a reference to the popover because it is managed by the presentation controller.
Code example (works both on iPhone and iPad):
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSour...
Java default constructor
...class constructor with no arguments". Uninitialised fields are initialised by other mechanisms also described in this reference. +1 to OrangeDog for providing a good reference.
– Superole
Jan 28 '14 at 8:38
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Why does PHP consider 0 to be equal to a string?
...e', or 'E' and the numeric value fits into integer type limits (as defined by PHP_INT_MAX), the string will be evaluated as an integer. In all other cases it will be evaluated as a float.
In this case the string is 'e' and thus it will be evaluated as a float:
The value is given by the initial...
Find size of an array in Perl
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The size of (1,2,3) is 3, and the indexes are (by default) 0, 1 and 2. So, $#arr will be 2 in this case, not 3.
– Nate C-K
Sep 13 '11 at 18:47
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