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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 .
...
Rails extending ActiveRecord::Base
...
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...
LINQ Single vs First
...ou mean the other.
Note: In my code, I will typically use FirstOrDefault() and SingleOrDefault() but that's a different question.
Take, for example, a table that stores Customers in different languages using a Composite Key ( ID, Lang ):
DBContext db = new DBContext();
Customer customer = db.Custome...
How to use JavaScript regex over multiple lines?
...to match all newlines, you would need to add \r as well to include Windows and classic Mac OS style line endings: (.|[\r\n]).
That turns out to be somewhat cumbersome, as well as slow, (see KrisWebDev's answer for details), so a better approach would be to match all whitespace characters and all no...
What does “=>” mean in PHP?
...the context of that foreach loop, it assigns the key of the array to $user and the value to $pass.
Example:
$user_list = array(
'dave' => 'apassword',
'steve' => 'secr3t'
);
foreach ($user_list as $user => $pass) {
echo "{$user}'s pass is: {$pass}\n";
}
// Prints:
// "dave's...
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...
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...
How to automatically crop and center an image
... any arbitrary image, I want to crop a square from the center of the image and display it within a given square.
7 Answers
...
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?
...
What can I use instead of the arrow operator, `->`?
... them inconsistently. Becomes really annoying when you work with templates and don't know the precise type.
– Konrad Rudolph
Oct 21 '08 at 10:15
1
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