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One of the more popular .NET providers for Postgresql is Npgsql, which is ADO.NET compatible and is used nearly identically as other .NET database providers. A typical query is performed by creating a command, binding parameters, and then executing the command. In C#: var connString = "Host=m...

You can use a For Each...Next loop to iterate through any IEnumerable type. This includes arrays, lists, and anything else that may be of type IEnumerable or returns an IEnumerable. An example of looping through a DataTable's Rows property would look like this: For Each row As DataRow In DataTable...

The following example shows how you can use Json.Net to serialize the data in an C# Object's instance, to JSON string. using System; using System.Collections.Generic; using Newtonsoft.Json; public class Employee { public string FirstName { get; set; } public string LastName { get; s...

The following example shows how you can deserialize a JSON string containing into an Object (i.e. into an instance of a class). using System; using System.Collections.Generic; using Newtonsoft.Json; public class Program { public class Employee { public s...

$customer = Customer::findOne(10); or $customer = Customer::find()->where(['id' => 10])->one(); or $customer = Customer::find()->select('name,age')->where(['id' => 10])->one(); or $customer = Customer::findOne(['age' => 30, 'status' => 1]); or $customer = C...

Detailed instructions on getting database set up or installed.

Creating a Custom Element with bindable properties is a snap. If you want to create an element that accepts one or more values which the plugin can use, the @bindable decorator and syntax is what you are looking for. Below, we are creating a custom element that accepts an array of fruits and displa...

In the following, we are creating an example of an Aurelia Custom Element which will allow you to display Youtube videos via their video ID. An Aurelia Custom Element can be defined in two different ways: the first one is by creating a viewmodel and accompanying view, the second one is by just cre...

A basic custom element is created in Aurelia based on naming conventions, by simply adding the suffix CustomElement to the name of a class. This suffix will automatically be stripped out by Aurelia. The remaining part of the class name will be lowercased and separated using a hyphen and can then be ...

First the setup for the example: import datetime as dt from sqlalchemy import Column, Date, Integer, Text, create_engine, inspect from sqlalchemy.orm import sessionmaker from sqlalchemy.ext.declarative import declarative_base Base = declarative_base() Session = sessionmaker() class User(B...

Given the following model class User(Base): __tablename__ = 'users' id = Column(Integer, primary_key=True) name = Column(Text, nullable=False) birthday = Column(Date) You can filter columns in the query: import datetime as dt session.query(User).filter(User.name == 'Bob')...

In SQLAlchemy core, the result is RowProxy. In cases where you want an explicit dictionary, you can call dict(row). First the setup for the example: import datetime as dt from sqlalchemy import ( Column, Date, Integer, MetaData, Table, Text, create_engine, select) metadata = MetaData() u...

Let's suppose we have a reference to the JQuery type definition and we want to extend it to have additional functions from a plugin we included and which doesn't have an official type definition. We can easily extend it by declaring functions added by plugin in a separate interface declaration with ...

Declare public variables and methods type in the interface to define how other typescript code can interact with it. interface ISampleClassInterface { sampleVariable: string; sampleMethod(): void; optionalVariable?: string; } Here we create a class that implements the interface. ...

Installation npm install -D webpack typescript ts-loader webpack.config.js module.exports = { entry: { app: ['./src/'], }, output: { path: __dirname, filename: './dist/[name].js', }, resolve: { extensions: ['', '.js', '.ts'], }, module: { loaders: [...

The engine is used to connect to different databases using a connection URL: from sqlalchemy import create_engine engine = create_engine('postgresql://user:pass@localhost/test') Note, however, that the engine does not actually establish a connection until it is first used. The engine automat...

You can open a connection (i.e. request one from the pool) using a context manager: with engine.connect() as conn: result = conn.execute('SELECT price FROM products') for row in result: print('Price:', row['price']) Or without, but it must be closed manually: conn = engine.co...

There are multiple ways to populate an array. Directly 'one-dimensional Dim arrayDirect1D(2) As String arrayDirect(0) = "A" arrayDirect(1) = "B" arrayDirect(2) = "C" 'multi-dimensional (in this case 3D) Dim arrayDirectMulti(1, 1, 2) arrayDirectMulti(0, 0, 0...

JSON data can also be read from files. Let's assume we have a file called data.json with the following content: [ { "Name" : "John Doe", "Standard" : 4 }, { "Name" : "Peter Parker", "Standard" : ...

Two-way Data-Binding supports the following attributes: ElementPropertiesAbsListViewandroid:selectedItemPositionCalendarViewandroid:dateCompoundButtonandroid:checkedDatePickerandroid:yearandroid:monthandroid:dayEditTextandroid:textNumberPickerandroid:valueRadioGroupandroid:checkedButtonRatingBarand...