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“open/close” SqlConnection or keep open?
...th static methods. Each of these methods opens/closes SQL connection when called:
6 Answers
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What's the fastest way to merge/join data.frames in R?
...(y) from main.d group by g1, g2"))
)
The outputs from the two benchmark call comparing the merge calculations are:
Joining by: x
test replications elapsed relative user.self sys.self user.child sys.child
3 data.table 1 0.34 1.000000 0.31 0.01 NA NA
2 ...
Xcode 6 Storyboard the wrong size?
...you to get used to size classes as they are the future, and you will eventually jump in anyway at some point."
You probably haven't added the layout constraints.
Select your label, tap the layout constraints button on the bottom:
On that menu add width and height (it should NOT be the same as...
Can a decorator of an instance method access the class?
I have something roughly like the following. Basically I need to access the class of an instance method from a decorator used upon the instance method in its definition.
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How to undo “git commit --amend” done instead of “git commit”
I accidentally amended my previous commit. The commit should have been separate to keep history of the changes I made to a particular file.
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Proper way to declare custom exceptions in modern Python?
...tionError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = errors
That way you could pass dict of error me...
Why do we use $rootScope.$broadcast in AngularJS?
... scope of that app can catch it using a simple: $scope.$on().
It is especially useful to send events when you want to reach a scope that is not a direct parent (A branch of a parent for example)
!!! One thing to not do however is to use $rootScope.$on from a controller. $rootScope is the applicati...
How to serve an image using nodejs
...
2016 Update
Examples with Express and without Express that actually work
This question is over 5 years old but every answer has some problems.
TL;DR
Scroll down for examples to serve an image with:
express.static
express
connect
http
net
All of the examples are also on GitHub: htt...
How do I force a DIV block to extend to the bottom of a page even if it has no content?
In the markup shown below, I'm trying to get the content div to stretch all the way to the bottom of the page but it's only stretching if there's content to display. The reason I want to do this is so the vertical border still appears down the page even if there isn't any content to display.
...
Stretch and scale CSS background
... background-size: cover;
}
cover means stretching the image either vertically or horizontally so it never tiles/repeats.
That would work for Safari 3 (or later), Chrome, Opera 10+, Firefox 3.6+, and Internet Explorer 9 (or later).
For it to work with lower verions of Internet Explorer, try th...