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Retrieve only the queried element in an object array in MongoDB collection
...her answers if you are using a more recent version of MongoDB.
The field selector parameter is limited to complete properties. It cannot be used to select part of an array, only the entire array. I tried using the $ positional operator, but that didn't work.
The easiest way is to just filter the ...
IntelliJ 13 - Add Navigate Back/Forward to toolbar?
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For some reason the toolbar is not visible by default.
In the View menu, select Toolbar. That should fix it.
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Is there an alternative sleep function in C to milliseconds?
... tv.tv_sec = milliseconds / 1000; tv.tv_usec = milliseconds % 1000 * 1000; select(0, NULL, NULL, NULL, &tv); instead of usleep(milliseconds * 1000);. Credit goes here.
– Josh Sanford
Sep 29 '16 at 18:18
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Eclipse does not highlight matching variables
...y:
window > preferences > java > editor > mark occurrences
Select all options available there.
Also go to:
Preferences > General > Editors > Text Editors > Annotations
Compare the settings for 'Occurrences' and 'Write Occurrences'
Make sure that you don't have the 'T...
C++ templates that accept only certain types
...that the compiler allows these, and then declare a variable my_template<char> z; and verify that it doesn't.
– j_random_hacker
Nov 16 '17 at 16:20
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How do you add an in-app purchase to an iOS application?
...he app you want do add the purchase to
Click the Features header, and then select In-App Purchases on the left
Click the + icon in the middle
For this tutorial, we are going to be adding an in-app purchase to remove ads, so choose non-consumable. If you were going to send a physical item to the user...
Code formatting shortcuts in Android Studio for Operation Systems
...System Settings → Keyboard → Shortcuts tab → System → Lock Screen.
Select the row New Accelerator..., then press any special key with the Alpha key (e.g. Shift + L). You should've successfully changed the keyboard shortcut.
Check if the keyboard shortcut now works in Android Studio.
Altern...
MySQL and GROUP_CONCAT() maximum length
...You should use it like this.
SET SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
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How can I find out if I have Xcode commandline tools installed?
...u will get an alert. You can verify that you have installed it by
$ xcode-select -p
/Library/Developer/CommandLineTools
And to be sure then enter $ gcc --version
You can read more about the process here: Xcode command line tools for Mavericks
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What's the difference between ASCII and Unicode?
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ASCII defines 128 characters, which map to the numbers 0–127. Unicode defines (less than) 221 characters, which, similarly, map to numbers 0–221 (though not all numbers are currently assigned, and some are reserved).
Unicode is a superset...