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To connect using java.sql.DriverManager you need a JDBC url to connect to your database. JDBC urls are database specific, but they are all of the form jdbc:<subprotocol>:<subname> Where <subprotocol> identifies the driver or database (for example postgresql, mysql, firebirdsql,...

When you deploy your app to a (Node.js-specific) hosted environment, this environment usually offers a PORT-environment variable that you can use to run your server on. Changing the port number to process.env.PORT allows you to access the application. For example, http.createServer(function(reques...

You can use the node-inspector. Run this command to install it via npm: npm install -g node-inspector Then you can debug your application using node-debug app.js The Github repository can be found here: https://github.com/node-inspector/node-inspector Debugging natively You can also debu...

Tips & Tricks to avoid nasty situations EC2 Instances and EBS Set IAM Roles. Unlike tags, the IAM Role is set once and for all on EC2 instanciation (even after 4 years) ! Try to identify and categorize beforehand your instances so you can give an them appropriate IAM roles. IAM Roles are ...

Problem: Some data needs to be passed to a scene loaded from a fxml. Solution Specify a controller using the fx:controller attribute and get the controller instance created during the loading process from the FXMLLoader instance used to load the fxml. Add methods for passing the data to the contr...

Problem: Some data needs to be passed to a scene loaded from a fxml. Solution Set the controller using the FXMLLoader instance used later to load the fxml. Make sure the controller contains the relevant data before loading the fxml. Note: in this case the fxml file must not contain the fx:contro...

LinqPad is a great tool that allows you to learn and test features of .Net languages (C#, F# and VB.Net.) Install LinqPad Create a new Query (Ctrl + N) Under language, select "C# statements" Type the following code and hit run (F5) string hw = "Hello World&quo...

In Elm, values are declared by writing a name, an equals sign, and then the actual value: someValue = 42 Functions are also values, with the addition of taking a value or values as arguments. They are usually written as follows: double n = n * 2 Every value in Elm has a type. The types of th...

A common task is to convert all columns of a data.frame to character class for ease of manipulation, such as in the cases of sending data.frames to a RDBMS or merging data.frames containing factors where levels may differ between input data.frames. The best time to do this is when the data is read ...

Rational represents a rational number as numerator and denominator: r1 = Rational(2, 3) r2 = 2.5.to_r r3 = r1 + r2 r3.numerator # => 19 r3.denominator # => 6 Rational(2, 4) # => (1/2) Other ways of creating a Rational Rational('2/3') # => (2/3) Rational(3) # => (3/1...

Ubuntu On recent Ubuntu versions, you can install an up-to-date version of CouchDB with sudo apt-get install couchdb. For older versions, such as Ubuntu 14.04, you should run: sudo add-apt-repository ppa:couchdb/stable -y sudo apt-get update sudo apt-get install couchdb -y Fedora To install ...

Each of Laravel's queue drivers are configured from the config/queue.php file. A queue driver is the handler for managing how to run a queued job, identifying whether the jobs succeeded or failed, and trying the job again if configured to do so. Out of the box, Laravel supports the following queue ...

Placeholders in the query string need to be set by using the set* methods: String sql = "SELECT * FROM EMP WHERE JOB = ? AND SAL > ?"; //Create statement to make your operations PreparedStatement statement = connection.prepareStatement(sql); statement.setString(1, "MANAGER&...

SQL Server Reporting Services can typically be installed with SQL Server installation media. An installation of SQL Server will be required, either locally or on a server. Starting with SQL Server 2008 R2, SSRS has the option to integrate with SharePoint instead of running a separate website.

Sometimes it's a good idea to further secure your publishes by requiring a user login. Here is how you achieve this via Meteor. import { Recipes } from '../imports/api/recipes.js'; import { Meteor } from 'meteor/meteor'; Meteor.publish('recipes', function() { if(this.userId) { return Re...

float literals are defined by using the suffix F or f, or by using a real number: float f = 30.5F;

let rec factorial n = match n with | 0 | 1 -> 1 | n -> n * (factorial (n - 1)) This function matches on both the values 0 and 1 and maps them to the base case of our recursive definition. Then all other numbers map to the recursive call of this function.

boot -d seancorfield/boot-new new -t app -n <appname> This command will tell boot to grab the task boot-new from https://github.com/seancorfield/boot-new and execute the task with the app template (see link for other templates). The task will create a new directory called <appname> wi...

Consider the following C# code Expression<Func<int, int>> expression = a => a + 1; Because the C# compiler sees that the lambda expression is assigned to an Expression type rather than a delegate type it generates an expression tree roughly equivalent to this code ParameterExpres...

Firebase Authentication allows the users of your app to sign-in with social providers or their email+password. But what if you want to store additional information about a user, beyond what Firebase Authentication allows you to specify? Or what if you want to display a list of the users in your app...