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How to Switch Active Cluster / Change Port in PostgreSQL in Linux

PostgreSQL Change Active Cluster Default Port

This article will demonstrate how to list the PostgreSQL clusters on your Linux system, and how to switch the active cluster. PostgreSQL is one of the most popular relation database servers. Multiple versions can be installed on the same host, so being able to switch between them is pretty useful. Read on to find out how to do it. What is a Cluster A PostgreSQL cluster is a collection of PostgreSQL databases with a shared configuration, managed. This configuration includes things like the executable that manages the … Read more

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Checking for Equality (And Inequality) in JavaScript, with Examples

Equality and Inequality JavaScript

This article will explain equality and inequality in the JavaScript Programming language, and provide code examples showing how to check if values are equal in value and type. Checking whether two values are equal can get a bit confusing in JavaScript – there is loose equality and strict equality involving types to consider. Read on to find out how testing for equality and inequality works in JavaScript. What are equality and inequality? In programming, equality is the process of checking whether two values are equal … Read more

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How to Import a CSV File to PostgreSQL

PostgreSQL Import CSV File

This tutorial will show you how to import data from a CSV file into a PostgreSQL database table. What is a CSV File A CSV (Comma Separated Values) file is a text file that contains tabulated information. The rows in this data each take up a line in the text file, while the values in each column on each row are separated by a comma – hence, comma-separated. CSV files are versatile. Because the data within is stored as plain text, they can be opened … Read more

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How to Export and Back Up PostgreSQL Databases

PostgreSQL Backup Import Export

This tutorial will show you how to export, import, and back up your PostgreSQL clusters and databases. You should regularly back up. It’s one of the most important things you can do as a sysadmin, developer, and even a hobbyist. Losing your data is detrimental to business, and your projects. Losing your family photos sucks too. This article demonstrates the various way to import and export PostgreSQL data so that it can be backed up. This process should be done regularly (or automated!), and performed … Read more

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Printing Text in Python Without a Newline

Python print without newline

This short tutorial will show you how to print text in Python, without a new line appearing. The Newline Character in Python In Python, newlines are represented by a \ (backslash) followed by n: \n You Can Add New Lines to Printed Strings The \n won’t be shown to the user – a new line will be inserted instead (unless an escape character is added). So, when the below code is executed: print(“Linux\nScrew”) It will appear as: Linux Screw Print Statements Add a Newline By Default By default, a newline … Read more

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How to Run an SQL File in MySQL (or MariaDB) on Linux/Ubuntu

How to Run a SQL File in MySQL/MariaDB on Linux/Ubuntu

Here is an article outlining several methods for running SQL files in MySQL on Linux/Ubuntu. Whether you’re installing a package, following a tutorial, or restoring a backup – it’s useful to be able to execute an SQL script from a file and have it do all of the work for you, rather than having to type it all out. Most GUI database managers have a simple import option prominently displayed in the menu bar – so here’s how to do it from the command line … Read more

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How to Read CSV Files in Python, With Examples

Python read from csv file

This article will show you how to read CSV (Comma Separated Values) files in the Python programming language, with examples. What is CSV (Comma Separated Values) CSV (Comma Separated Values) is a format for storing and transmitting data, usually in a text file, in which the individual values are separated by a comma (,). Each row in a CSV file represents an individual record containing multiple comma separated values. A CSV file looks like this: name,age,favourite colour Fred,54,green Mary,31,pink Steve,12,orange Above, the CSV describes three people, with information … Read more

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Python setAttr() – What it Does and How to Use It [Examples]

Python use setattr() to set object attributes

The setattr() function is used to set the value of an attribute of an object. Here is how it is used, with examples. Python Objects and Classes Python is an object oriented programming language. Object oriented means that rather than code being written as a list of instructions, accumulating data and passing the results to the following lines of code (known as procedural programming), data and functionality is contained within the objects it describes. Each object is a self-contained representation of something, that can be modified, and passed between functions … Read more

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JavaScript for Loops – How to Use Them [Examples]

How to use for loops in JavaScript

This article will show you how to use the simplest JavaScript loop – the for loop, and provide code examples. JavaScript for Loops JavaScript’s for loops are used to execute a block of code repeatedly until a condition is met. The initial variables, condition that must be met, and the expression which progresses the loop are all defined within the loop expression. for loop Syntax JavaScript for loops follow the following syntax: for (INITIALIZATION; CONDITION; FINAL_EXPRESSION) { //Code to be executed in the loop } Note that: INITIALIZATION sets the variable which is used to control … Read more

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How to Sort a Dictionary by Value in Python [Examples]

Python sort dictionary by value

This article will show you how to sort a dictionary by the values it contains in the Python programming language. Code examples are included. What is a Dictionary? A dictionary is one of Pythons built in variable types for storing data. Dictionaries are similar to associative arrays or hash tables in other languages. A dictionary contains a collection of values or objects. Unlike lists and arrays, rather than their values being stored at a specific index (the ordered position in the sequence of stored values), values in a dictionary … Read more