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When creating a model for a table that has a composite primary key, additional work is required on the Object for the model Entity to respect those constraints. The following example SQL table and Entity demonstrates the structure to store a review left by a customer for an item in an online store....

Occasionally it's useful to assign one or more ports manually vs using the defaults. Doing so can solve port availability/permissions issues or accommodate running more than one ember instance at a time. To have ember-cli attempt to identify and assign an available port, use: ember serve --port ...

The code example below demonstrate how you can get a lighter and darker shade of a given color, useful in applications having dynamic themes For Darker Color + (UIColor *)darkerColorForColor:(UIColor *)c { CGFloat r, g, b, a; if ([c getRed:&r green:&g blue:&b alpha:&a]) ...

In Sprite-Kit, there is the concept of collisions which refers to the SK physics engine handling how physics objects interact when they collide i.e. which ones bounce off which other ones. It also has the concept of contacts, which is the mechanism by which your program gets informed when 2 physics...

y ~ . : Here . is interpreted as all variables except y in the data frame used in fitting the model. It is equivalent to the linear combinations of predictor variables. For example y ~ var1 + var2 + var3+...+var15 y ~ . ^ 2 will give all linear (main effects) and second order interaction terms of t...

There is a way to simplify defining autolayout for views using VFL. It may seem hard at first, but it is actually really easy to use. Some definitions first: | represents superview H: or V: represent current orientation - horizontal or vertical view names should be enclosed in square brackets ...

Checkpointing configuration is done in two steps. First, you need to choose a backend. Then, you can specify the interval and mode of the checkpoints in a per-application basis. Backends Available backends Where the checkpoints are stored depends on the configured backend: MemoryStateBackend...

A savepoint stores two things: (a) the positions of all datasources, (b) the states of operators. Savepoints are useful in many circonstances: slight application code updates Flink update changes in parallelism ... As of version 1.3 (also valid for earlier version): checkpoint must be ...

You'll often want to assign something to an object if it is None, indicating it has not been assigned. We'll use aDate. The simplest way to do this is to use the is None test. if aDate is None: aDate=datetime.date.today() (Note that it is more Pythonic to say is None instead of == None.) ...

Run-time memory management with Rc can be very useful, but it can also be difficult to wrap one's head around, especially if your code is very complex and a single instance is referenced by tens or even hundreds of other types in many scopes. Writing a Drop trait that includes println!("Droppi...

A SIMPLE TEMPLATE Let’s start with a very simple template that shows our name and our favorite thing: <div> Hello my name is {{name}} and I like {{thing}} quite a lot. </div> {}: RENDERING To render a value, we can use the standard double-curly syntax: My name is {{name}} P...

Processing provides the method triangle in order to draw a triangle. The code below draws a nearly equilateral triangle of 25 pixels between each defining point. void setup() { size(500, 500); background(0); } void draw() { triangle(0, 0, 25, 0, 12, 12); } The signature of tria...

The interactive mode The most basic way to use R is the interactive mode. You type commands and immediately get the result from R. Using R as a calculator Start R by typing R at the command prompt of your operating system or by executing RGui on Windows. Below you can see a screenshot of an inter...

Each standard Oracle error is associated with an error number. Its important to anticipate what could go wrong in your code. Here for a connection to another database it can be: -28000 account is locked -28001 password expired -28002 grace period -1017 wrong user / password Here is a way to...

To illustrate this, here is a function that has 3 different "wrong" behaviors parameter is completely stupid: we use a user-defined expression parameter has a typo: we use Oracle standard NO_DATA_FOUND error another, but not handled case Feel free to adapt it to your standards: DE...

You can use the ng generate or ng g command to generate Angular building blocks (components, services, pipes, etc.). You can find all possible blueprints in the table below: ScaffoldUsageShortenedComponentng generate component component-nameng g c component-nameDirectiveng generate directive direc...

class MyToolbarControl { public: MyToolbarControl(HWND hWndToolbar, HWND hWndNotifyParent = nullptr) : _Handle(hWndToolbar) { if (hWndNotifyParent == nullptr) { hWndNotifyParent = GetAncestor(hWndToolbar, GA_ROOTOWNER); } SetWindowSubclass( ...

Example of usage: /* Instance of your custom APNs/local notification manager */ private var pushManager: AppleNotificationManager! Registration: func application(application: UIApplication, didRegisterUserNotificationSettings notificationSettings: UIUserNotificationSettings) { // Called...

To enable Pull to Refresh in a ListView in Xamarin, you first need to specify that it is PullToRefresh enabled and then specify the name of the command you want to invoke upon the ListView being pulled: <ListView x:Name="itemListView" IsPullToRefreshEnabled="True" RefreshComm...

I'm in a controlled room with a single minew beacon that use IBEACON protocol. BLEController needs to extend CBPeripheralDelegate I'll use the first BLE to connect after the search has stop. Modify the method StopSearchBLE() class BLEController: CBCentralManagerDelegate, CBPeripheralDelegate...