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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...
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.
...
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
...
Is there a “theirs” version of “git merge -s ours”?
...ork as expected.
Of course, doing the actual removal with the git rm command will prevent the conflict from happening in the first place.
Note: A longer form option also exists.
To use it, replace:
-X theirs
with:
--strategy-option=theirs
...
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 .
...
Covariance and contravariance real world example
I'm having a little trouble understanding how I would use covariance and contravariance in the real world.
9 Answers
...
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...
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.
...
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)...
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...