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How to resize a VirtualBox vmdk file
I've run out of space on a virtual machine disk which is a vmdk and need to resize the virtual image. Resizing with the command
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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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Retrieve specific commit from a remote Git repository
... on my PC? The structure of remote repo is absolutely same as that of mine and hence there won't be any conflicts but I have no idea how to do this and I don't want to clone that huge repository.
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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 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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How to flatten tree via LINQ?
...er style", convert Flatten to a generic extension method that takes a tree and a function that produces descendants from a node:
public static IEnumerable<T> Flatten<T>(
this IEnumerable<T> e
, Func<T,IEnumerable<T>> f
) => e.SelectMany(c => f(c).Flatten(f)...
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...
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 detect if multiple keys are pressed at once using JavaScript?
I'm trying to develop a JavaScript game engine and I've came across this problem:
13 Answers
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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...