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Should I index a bit field in SQL Server?
...ng a field with low cardinality (a low number of distinct values) is not really worth doing. I admit I don't know enough about how indexes work to understand why that is.
...
How to work with Git branches and Rails migrations
...s and many of them include db migrations. We try to be careful but occasionally some piece of code in master asks for a column that got removed/renamed in another branch.
...
Why are these constructs using pre and post-increment undefined behavior?
...fined behavior here as well since the program is modifying variables(i, u, etc..) more than once between sequence points. From draft standard section 6.5 paragraph 2(emphasis mine):
Between the previous and next sequence point an object shall have its stored value
modified at most once by the ...
How to get the response of XMLHttpRequest?
...
I'd suggest looking into fetch. It is the ES5 equivalent and uses Promises. It is much more readable and easily customizable.
const url = "https://stackoverflow.com";
fetch(url)
.then(
response => response.text() // .json(), etc...
Create objective-c class instance by name?
... you are working with Objective-C without the NeXTstep (OS X, iOS, GNUstep etc) system or you just think this method is cleaner, then you could utilize the Objective-C language runtime library's API. Under Objective-C 2.0:
#import <objc/runtime.h>
//Declaration in the above named file
id ob...
Changing Vim indentation behavior by file type
...h a width of 2 characters for indenting (the noexpandtab option is set globally elsewhere in my configuration).
This is described here: http://vimdoc.sourceforge.net/htmldoc/usr_05.html#05.4, scroll down to the section on filetype plugins.
...
Named regular expression group “(?Pregexp)”: what does “P” stand for?
...string as that matched by the group named
"foo". Equivalent to \1, \2, etc. except that the group is referred
to by name, not number.
I hope that this Python-specific extension won't conflict with any
future Perl extensions to the Perl regex syntax. If you have plans to
use (?P, plea...
Fit image into ImageView, keep aspect ratio and then resize ImageView to image dimensions?
...nsity);
}
The xml code for the ImageView:
<ImageView a:id="@+id/image_box"
a:background="#ff0000"
a:src="@drawable/star"
a:layout_width="wrap_content"
a:layout_height="wrap_content"
a:layout_marginTop="20dp"
a:layout_gravity="center_horizontal"/>
Thanks to this di...
Escaping keyword-like column names in Postgres
...(registered by Postgres) as the name of Table, Schema, Function or Trigger etc, you must have to use either double quotes, or you can specify schema name with dot concatenation.
Let's Suppose, order is the keyword registered by Postgres. And in some scenarios, you must have to use this keyword as a...
How do I set up a simple delegate to communicate between two view controllers?
... super.viewDidLoad()
}
@IBAction func btnSendDataPushed(_ sender: UIButton) {
// Call the delegate method from SecondVC
self.delegate?.sendData(data:self.data)
dismiss(animated: true, completion: nil)
}
}
ViewCo...