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When to use in vs ref vs out
...ss you need ref.
It makes a big difference when the data needs to be marshalled e.g. to another process, which can be costly. So you want to avoid marshalling the initial value when the method doesn't make use of it.
Beyond that, it also shows the reader of the declaration or the call whether the ...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
...
You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
Give all the permissions to a user on a DB
I would like to give an user all the permissions on a database without making it an admin.
The reason why I want to do that is that at the moment DEV and PROD are different DBs on the same cluster so I don't want a user to be able to change production objects but it must be able to change objects on...
Create subdomains on the fly with .htaccess (PHP)
...ches[1])) {
$subdomain = $matches[1];
}
I have used regex here to to allow for people hitting your site via www.subdomain.example.org or subdomain.example.org.
If you never anticipate having to deal with www. (or other subdomains) then you could simply use a substring like so:
$subdomain = s...
Retrieve the position (X,Y) of an HTML element relative to the browser window
...supported this since as long as you are likely to care about and it was finally standardized in CSSOM Views. All other browsers adopted it a long time ago.
Some browsers also return height and width properties, though this is non-standard. If you're worried about older browser compatibility, che...
Change string color with NSAttributedString?
...
There is no need for using NSAttributedString. All you need is a simple label with the proper textColor. Plus this simple solution will work with all versions of iOS, not just iOS 6.
But if you needlessly wish to use NSAttributedString, you can do something like this:
...
Create an index on a huge MySQL production table without table locking
...d or dropped. The CREATE INDEX or DROP INDEX statement only finishes after all transactions that are accessing the table are completed, so that the initial state of the index reflects the most recent contents of the table. Previously, modifying the table while an index is being created or dropped ty...
How to use ArrayAdapter
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...
C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...