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How to find whether or not a variable is empty in Bash
...o, there is a difference between "empty" and "unset". See How to tell if a string is not defined in a Bash shell script.
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MySQL COUNT DISTINCT
...love SQL because you get questions like "How do I count distinct user IDs" and the answer is just "Count(Distinct user_id)"
– Tim
Nov 13 '18 at 15:29
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Programmatically change log level in Log4j2
...er names from the loggers themselves rather than hard coding the name as a string.
– DWoldrich
Oct 29 '19 at 18:45
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jQuery .on('change', function() {} not triggering for dynamically created inputs
The problem is that I have some dynamically created sets of input tags and I also have a function that is meant to trigger any time an input value is changed.
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Mongod complains that there is no /data/db folder
..., e.g. sudo mkdir -p /data/db
Or you need to do su - to become superuser, and then create the directory with mkdir -p /data/db
Note:
MongoDB also has an option where you can create the data directory in another location, but that's generally not a good idea, because it just slightly complicate...
Do NSUserDefaults persist through an Update to an app in the Appstore?
...a, NSUserDefaults is the best way to save data such as preferences, dates, strings etc. If you are looking to save images and files, the file system is a better bet.
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What's the difference between “declare class” and “interface” in TypeScript
...n we have the following interface:
interface test {
foo: number,
bar: string,
}
The objects which we define which have this interface type need to match the interface exactly:
// perfect match has all the properties with the right types, TS compiler will not complain.
const obj1: test = { ...
Is there a way to crack the password on an Excel VBA Project?
...te Declare Function GetModuleHandleA Lib "kernel32" (ByVal lpModuleName As String) As Long
Private Declare Function GetProcAddress Lib "kernel32" (ByVal hModule As Long, _
ByVal lpProcName As String) As Long
Private Declare Function DialogBoxParam Lib "user32" Alias "DialogBoxParamA" (ByVa...
PopupWindow - Dismiss when clicked outside
...with my activity (say scrolling on my list). I can scroll through my list and the PopupWindow is still there.
15 Answers
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Validation of radio button group using jQuery validation plugin
...l you have to do is set one of the members of the radio set to be required and jquery will take care of the rest:
<input type="radio" name="myoptions" value="blue" class="required"> Blue<br />
<input type="radio" name="myoptions" value="red"> Red<br />
<input type="radio"...