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PadLeft function in T-SQL
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SQL Server now supports the FORMAT function starting from version 2012, so:
SELECT FORMAT(id, '0000') FROM TableA
will do the trick.
If your id or column is in a varchar and represents a number you convert first:
SELECT FORMAT(CON...
explicit casting from super class to subclass
... you're essentially telling the compiler "trust me. I'm a professional, I know what I'm doing and I know that although you can't guarantee it, I'm telling you that this animal variable is definitely going to be a dog."
Since the animal isn't actually a dog (it's an animal, you could do Animal anima...
HTTP redirect: 301 (permanent) vs. 302 (temporary)
...not attempt to request the original location but use the new location from now on.
Status 302 means that the resource is temporarily located somewhere else, and the client/browser should continue requesting the original url.
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Summarizing multiple columns with dplyr? [duplicate]
...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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How can I get the console logs from the iOS Simulator?
...Then run the simulator.
EDIT:
This stopped working on Mavericks/Xcode 5. Now you can access the simulator logs in its own folder: ~/Library/Logs/iOS Simulator/<sim-version>/system.log
You can either use the Console.app to see this, or just do a tail (iOS 7.0.3 64 bits for example):
tail -f...
Timer function to provide time in nano seconds using C++
...e QueryPerformanceCounter. And here is more on QPC
Apparently there is a known issue with QPC on some chipsets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states:
QueryPerformance...
How to get start and end of day in Javascript?
...0 * 60 * 24; // 24 hours in milliseconds
let startOfDay = Math.floor(Date.now() / interval) * interval;
let endOfDay = startOfDay + interval - 1; // 23:59:59:9999
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get UTC time in PHP
... DateTimeZone.
The DateTime __construct() documentation suggests passing "now" as the first parameter when creating a DateTime instance and specifying a timezone to get the current time.
$date_utc = new \DateTime("now", new \DateTimeZone("UTC"));
echo $date_utc->format(\DateTime::RFC850); # Sa...
How to implement onBackPressed() in Fragments?
...pBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
}
Since now, we will work on our code BaseActivity and its fragments
Create private listener on top of your class BaseActivity
protected OnBackPressedListener onBackPressedListener;
create method to set listener in BaseActivity
pu...
How do Python functions handle the types of the parameters that you pass in?
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Python is strongly typed because every object has a type, every object knows its type, it's impossible to accidentally or deliberately use an object of a type "as if" it was an object of a different type, and all elementary operations on the object are delegated to its type.
This has nothing to ...