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A site for Linux lovers worldwide. For newbies, system engineers, administrators, and everybody in between. We cover all things Linux, plus various programming languages, including Python, Javascript, and PHP.

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How to Convert a USB Printer to Wireless with a Raspberry Pi
How to Use a Raspberry Pi for Digital Signage
The Worst Things You’ll Probably Google As a Programmer on Linux
How to Build a Raspberry Pi Internet Kiosk
Browsing the Internet on a 1989 Macintosh II with a Web Rendering Proxy
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Is PostgreSQL an SQL or NoSQL Database?

PostgreSQL is not NoSQL

A common question is whether PostgreSQL is an SQL or NoSQL database (it’s not) – this article explains why. What is SQL SQL (pronounced sequel or S-Q-L) is the Structured Query Language – a language used by many relational database systems for querying data. It is also increasingly being used for defining data schemas in data analytics applications where the data is not stored in a database but is arriving as a data stream. Data defined and queried by SQL is structured tables that can have relationships between records – for example … Read more

How to Include a JavaScript File in Another JavaScript File [Examples]

How to Include a JavaScript File in Another

This article will detail the various methods for including a JavaScript file in another JavaScript file – providing several methods for use in the browser, and when working in Node.js. One of the cornerstones of programming is reusable code. This concept is encapsulated in the DRY (Don’t Repeat Yourself) principle – that if you need to do something multiple times, you write the code for it once, and re-use it where it is required, rather than having multiple copies of the same code in your code base. … Read more

JavaScript Reference: Complete List of Operators + Examples

JavaScript Operators

This article will explain and list JavaScript operators and expressions. JavaScript operators perform a given operation on the provided expressions or values. Common operations include comparisons, arithmetic, and ternary operations. You will use JavaScript operators frequently (even the simplest JavaScript code will use multiple operators!), so it’s worth getting to know them, and their expected behaviour. What are Operators and Operands? Javascript operators perform a given operation, for example addition, subtraction, and other arithmetic, comparisons like greater than/less than, and more complicated operations like ternary/comparison … Read more

PHP Scopes in Functions, Loops, Modules, With Examples

PHP Variable Scopes

This article explains what variable scopes are, and how they work in the PHP programming language, with code examples. When programming in any language, you must be aware of how variables are scoped – otherwise, you risk unexpected behaviour, including incorrect calculations, or loss of data – detrimental outcomes for any application (especially if you are working with business records or financial data) that will result in angry users. What is a Variable? In computer programming, a variable stores a value, giving it a name that can … Read more

Categories PHP

Python NumPy Crash Course – A Simple Tutorial and Example

Python Numpy Course Tutorial Example

Python’s NumPy library is the standard for working with numerical data. This article will explain why that is, and how to use it. In addition to this, code examples for basic usage will be shown, and we will build a real-world example that implements NumPy to work with some example data. Python and Arrays Whether you are working with data collected for scientific or business reasons, it is usually collected in the form of arrays of data presented as tables with single or multiple columns. … Read more

Python Virtual Environments with virtualenv and Anaconda

python virtualenv

This article will explain and demonstrate virtual environments in Python using virtualenv and in Anaconda. What is a ‘Virtual Environment’? In Python, a virtual environment is an isolated directory that contains all of the dependencies of a Python project. By default, when you install a package using the pip package manager, it is installed globally – that version of the package is available to all Python scripts running on your system. This can cause problems. It clutters up your global Python installation, and all projects … Read more

PHP $this Variable – What It Is, How To Use It [Examples]

PHP this

This article will explain the PHP $this variable – what it is, what it does, and how to use it – with code examples. PHP Objects and Classes PHP is an object-oriented programming language. Code and data can be stored in an object which represents the items your code represents with a set of properties and methods. For example, you might have objects that represent sales invoices, or cars, or pets, or people – each containing code and data relevant to the thing they represent. The properties or attributes of … Read more

Categories PHP

How to Use Variable Variables in PHP, with Examples

PHP Variable Variables

Variable variables let you dynamically access variables by their name. Sound confusing? This article will explain PHP variable variables, and provide code examples. What is a variable? In computer programming, variables store a value, or reference to a value, for later use. Variables have names, and when you access a named variable, the value it contains can be read or updated. Declaring variables in PHP In PHP, a variable is declared when it is first used: Above, a variable named $myVariable is declared using the = (equals) operator, and assigned the … Read more

Categories PHP

Top 3 Best (FREE) GUIs for PostgreSQL in 2022

PostgreSQL Best GUI

PostgreSQL is one of the most popular database systems in use today. GUIs make working with data in PostgreSQL simpler for beginners – here are the best free GUIs you can use on Linux in 2022. What is PostgreSQL PostgreSQL is an object-relational database management system (ORDBMS) for storing structured data. It provides a networked database server that can be used as the backend for your mobile apps, APIs, and webapps. It is also used for storing data for processing in analytics and data science. It’s free to … Read more

How to Check that PostgreSQL Server is Running on Linux (Ubuntu/Debian/Red Hat/Fedora)

Check PostgreSQL Server Running

This tutorial will show you how to check that the PostgreSQL Server service is running on your Linux system. To install PostgreSQL follow our tutorial here. Checking PostgreSQL is Running on Ubuntu/Debian To check whether the PostgreSQL server service is running successfully on your Debian or Ubuntu system, run: Checking the Firewall By default PostgreSQL runs on port 5432 and is not restricted by host name. When installing PostgreSQL on Ubuntu, usually a firewall rule will be created automatically allowing access to the database server. You can confirm … Read more