Tutorial by Examples

Note in this example we will use PostgreSQL DBMS, but you can use any DBMS We will use a database bd_test witch contain a Schema: sch_test and two tables users and test : CREATE TABLE sch_test.users ( id serial NOT NULL, username character varying, password character varying, CONSTRAI...

BFS can be used to find the connected components of an undirected graph. We can also find if the given graph is connected or not. Our subsequent discussion assumes we are dealing with undirected graphs.The definition of a connected graph is: A graph is connected if there is a path between every p...

HTML: <div class="wrapper"> <div class="content"></div> </div> CSS: .wrapper{ min-height: 600px; } .wrapper:before{ content: ""; display: inline-block; height: 100%; vertical-align: middle; } .content { display...

The new Bootstrap 4 Navbar Component is improved over it’s Bootstrap 3.x predecessor. In Bootstrap 4, the Navbar is responsive by default and utilizes flexbox to make alignment of Navbar content much easier. It’s also a simple matter of using the new navbar-toggleable-* classes to change the Navbar ...

var EmberApp = require('ember-cli/lib/broccoli/ember-app'); module.exports = function(defaults) { var app = new EmberApp(defaults, { // Add options here datatables: { core: true, style: 'bs', extensions: [ { name: 'buttons', extensions: ['colVi...

Suppose we'd like to invoke the JavaScript function JSON.stringify which receives an object, encodes it into a JSON string and returns it. All we'd have to do is write the function signature, mark it as external and annotate it with the @JS annotation: @JS("JSON.stringify") external St...

Suppose we'd like to wrap the Google Maps JavaScript API google.maps: @JS('google.maps') library maps; import "package:js/js.dart"; @JS() class Map { external Map(Location location); external Location getLocation(); } We now have the Map Dart class which corresponds to t...

It's common practice in JavaScript to pass object literals to functions: // JavaScript printOptions({responsive: true}); Unfortunately we cannot pass Dart Map objects to JavaScript in these cases. What we have to do is create a Dart object that represents the object literal and contains all of...

Install pip : $ pip install django-cassandra-engine Add Getting Started to INSTALLED_APPS in your settings.py file: INSTALLED_APPS = ['django_cassandra_engine'] Cange DATABASES setting Standart: Standart DATABASES = { 'default': { 'ENGINE': 'django_cassandra_engine', ...

Go to https://www.blender.org/download/ Choose your operating system Click the proper mirror next to the version of blender for your operating system. You can usually just click the mirror closest to your current location. (more info) Also, at the bottom of the page are also...

In this example, we use this database: "your-project-name" : { "users" : { "randomUserId1" : { "display-name" : "John Doe", "gender" : "male" } "randomUserId2" :...

Note: You need to know which data referenced by getReference() first before you can completely understand this example. There are three common method to get your data from Firebase Realtime Database: addValueEventListener() addListenerForSingleValueEvent() addChildEventListener() When w...

import android.os.Bundle; import android.os.Handler; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.Toolbar; import android.util.Log; import android.widget.T...

Step 1 - installing VirtualBox Download and install VirtualBox according to your operating system. , it is required to run Genymotion. Step 2 - downloading Genymotion Go to the Genymotion download page and download Genymotion according to your operating system. Note: you will need to create a ...

Many developers have this problem when they work on huge projects, especially if they work on some modular CMS on plugins, addons, components etc. Here is solution for safe session start where if first checked PHP version to cover all versions and on next is checked if session is started. If session...

import sys from PyQt4 import QtGui def window(): app = QtGui.QApplication(sys.argv) w = QtGui.QWidget() b = QtGui.QLabel(w) b.setText("Hello World!") w.setGeometry(100,100,200,50) b.move(50,20) w.setWindowTitle("PyQt") w.show() sys.exit(app...

Throwable has two direct subclasses, Exception and Error. While it's possible to create a new class that extends Throwable directly, this is inadvisable as many applications assume only Exception and Error exist. More to the point there is no practical benefit to directly subclassing Throwable, as ...

If developers want to test Google Maps or any other Google service like Gmail,Youtube, Google drive etc. then they first need to install Google framework on Genymotion. Here are the steps:- 4.4 Kitkat 5.0 Lollipop 5.1 Lollipop 6.0 Marshmallow 7.0 Nougat 7.1 Nougat (webview patch) Download fro...

A namespace can be given an alias (i.e., another name for the same namespace) using the namespace identifier = syntax. Members of the aliased namespace can be accessed by qualifying them with the name of the alias. In the following example, the nested namespace AReallyLongName::AnotherReallyLongNam...

Call this function with parameter argument as array with type 'any'. It will return you json string. Json string is used to submit array in web service call as request input parameter in Swift. //----------------------- let array = [["one" : 1], ["two" : 2], ["three" ...