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Best way to test SQL queries [closed]
...onth as
select *, year * 12 + month as absolute_month from month_value;
Now what we have to test is inherent in our spec, namely that for any tuple (year, month), there is one and only one (absolute_month), and that (absolute_month)s are consecutive. Let's write some tests.
Our test will be a SQ...
Java using enum with switch statement
...ue and then switch on the enum value.
enum GuideView {
SEVEN_DAY,
NOW_SHOWING,
ALL_TIMESLOTS
}
// Working on the assumption that your int value is
// the ordinal value of the items in your enum
public void onClick(DialogInterface dialog, int which) {
// do your own bounds checking...
Django Passing Custom Form Parameters to Formset
...
this should be correct way of doing it now. the accepted answer works and is nice but is a hack
– Junchao Gu
Nov 3 '17 at 9:36
...
Differences in boolean operators: & vs && and | vs ||
I know the rules for && and || but what are & and | ? Please explain these to me with an example.
11 Ans...
List or IList [closed]
...ays writeable and thus always keeps its promises. Also, since .NET 4.6, we now have IReadOnlyCollection<T> and IReadOnlyList<T> which are almost always better fits than IList<T>. And they are covariant. Avoid IList<T>!
– ZunTzu
Nov 10 '1...
Can a C++ enum class have methods?
...IsYellow() const { return value == Banana; }
private:
Value value;
};
Now you can write:
Fruit f = Fruit::Strawberry;
f.IsYellow();
And the compiler will prevent things like:
Fruit f = 1; // Compile time error.
You could easily add methods such that:
Fruit f("Apple");
and
f.ToString(...
Center a popup window on screen?
...lso work on windows that aren't maxed out to the screen's width and height now thanks to @Frost!
If you're on dual monitor, the window will center horizontally, but not vertically... use this function to account for that.
const popupCenter = ({url, title, w, h}) => {
// Fixes dual-screen po...
How to detect orientation change?
...on while using the camera with AVFoundation, and found that the didRotate (now deprecated) & willTransition methods were unreliable for my needs. Using the notification posted by David did work, but is not current for Swift 3.x/4.x.
Swift 4.2
The notification name has been changed.
The closure...
Can you give a Django app a verbose name for use throughout the admin?
... listed below.
Django 1.7
As stated by rhunwicks' comment to OP, this is now possible out of the box since Django 1.7
Taken from the docs:
# in yourapp/apps.py
from django.apps import AppConfig
class YourAppConfig(AppConfig):
name = 'yourapp'
verbose_name = 'Fancy Title'
then set th...
How do I change selected value of select2 dropdown with JqGrid?
...irst I initialize select2 on my select:
$('#my-best-friend').select2();
Now I manually select Bob in the browser. Next Bob does something naughty and I don't like him anymore. So the system unselects Bob for me:
$('#my-best-friend').val('').trigger('change');
Or say I make the system select th...