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How much size “Null” value takes in SQL Server
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The smallest addressable unit of memory in most computer systems is one byte (typically 8 bits). So in reality, a bit takes a byte. Great answer Mark: +1.
– JohnB
Sep 16 '10 at 22:23
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Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
Python Regex instantly replace groups
Is there any way to directly replace all groups using regex syntax?
2 Answers
2
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Long press gesture on UICollectionViewCell
...ILongPressGestureRecognizer *lpgr
= [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.delegate = self;
lpgr.delaysTouchesBegan = YES;
[self.collectionView addGestureRecognizer:lpgr];
}
-(void)handleLongPress:...
Why use make over a shell script?
...t would be a lot more work (explicitly checking the last-modified dates on all the files, etc.) The only obvious alternative with a shell script is to rebuild everything every time. For tiny projects this is a perfectly reasonable approach, but for a big project a complete rebuild could easily take ...
Single Line Nested For Loops
...ertools.product, which returns an iterable yielding tuples of values from all the iterables you pass it. That is, itertools.product(A, B) yields all values of the form (a, b), where the a values come from A and the b values come from B. For example:
import itertools
A = [50, 60, 70]
B = [0.1, 0.2...
How do you clear a slice in Go?
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It all depends on what is your definition of 'clear'. One of the valid ones certainly is:
slice = slice[:0]
But there's a catch. If slice elements are of type T:
var slice []T
then enforcing len(slice) to be zero, by the a...
Java `final` method: what does it promise?
...method can't be overridden (for object scope) or hidden (for static). This allows the original developer to create functionality that cannot be changed by subclasses, and that is all the guarantee it provides.
This means that if the method relies on other customizable components like non-public fie...
mysql create user if not exists
...alhost' IDENTIFIED BY 'password';
Note that the 5.7.6 method doesn't actually grant any permissions.
If you aren't using a version which has this capability (something below 5.7.6), you can do the following:
GRANT ALL ON `database`.* TO 'user'@'localhost' IDENTIFIED BY 'password';
This will ...
Finding the handle to a WPF window
Windows forms had a property win1.Handle which, if I recall, returns the handle of the main window handle?
4 Answers
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