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Rails extending ActiveRecord::Base
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Create a file in the config/initializers directory called extensions.rb and add the following line to the file:
require "active_record_extension"
Inheritance (Preferred)
Refer to Toby's answer.
Monkey patching (Should be avoided)
Create a file in the config/initializers directory called act...
How does this CSS produce a circle?
...f 180 pixels?
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source):
The height and width apply only on content, if the correct box model is being used (no quirks mode, no old Internet Explorer).
Where d...
SQL how to make null values come last when sorting ascending
...e with a datetime field. The field in question can be null. I have a query and I want the results sorted ascendingly by the datetime field, however I want rows where the datetime field is null at the end of the list, not at the beginning.
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What is the difference between Python's list methods append and extend?
What's the difference between the list methods append() and extend() ?
20 Answers
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How to properly create composite primary keys - MYSQL
... gross oversimplification of an intense setup I am working with. table_1 and table_2 both have auto-increment surrogate primary keys as the ID. info is a table that contains information about both table_1 and table_2 .
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What does “error: option --single-version-externally-managed not recognized” indicate?
...not recognized when pip install ing varions packages (including PyObjC and astropy ). I've never seen this error before, but it's now also showing up on travis-ci builds for which nothing has changed.
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How can I get Visual Studio 2008 Windows Forms designer to render a Form that implements an abstract
I engaged a problem with inherited Controls in Windows Forms and need some advice on it.
10 Answers
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Calculating frames per second in a game
...asiest way is to take the current answer (the time to draw the last frame) and combine it with the previous answer.
// eg.
float smoothing = 0.9; // larger=more smoothing
measurement = (measurement * smoothing) + (current * (1.0-smoothing))
By adjusting the 0.9 / 0.1 ratio you can change the 'tim...
How to disable text selection highlighting
... located on the top of the Stack Overflow page) or tabs, is there a CSS standard way to disable the highlighting effect if the user accidentally selects the text?
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Creating a segue programmatically
...iew controller (base class) that will transition to a new view controller, and will be inherited by all derived classes. You could do this by creating a method like this one to your base class view controller:
- (IBAction)pushMyNewViewController
{
MyNewViewController *myNewVC = [[MyNewViewCont...