This SQLite Linux tutorial is intended for beginners who wish to learn how to get started with SQLite database. SQLite is one of the world’s most widely-used Database programs. So, what is a Database, and what is SQLite?
database
Migrate WordPress multisite to new server
WordPress is a free and open source Content Management System written in PHP and is what a vast segment of websites is based on. The platforms has a vary nice feature: it allows the creation and management of multiple websites from the same installation. While migrating a WordPress installation is quite easy, to migrate WordPress multisite to a new server requires additional steps. In this tutorial we see how to proceed.
Saving an output of PostgreSQL query to a text file
When using PostgreSQL on Linux, there may be times that you wish to save the output of a query. Normally, the output appears on your screen. It’s possible to redirect this output to a file instead, which would allow you to view it later. In this guide, we’ll show you how to save the output of a PostgreSQL query to a file.
In this tutorial you will learn:
- How to save the output of a PostgreSQL query to a file
Linux commands to back up and restore MySQL database
It’s always a good idea to take frequent backups of your MySQL or MariaDB databases. They can potentially contain thousands of lines of irreplaceable data. Many users may be confused on how to back up their databases at first, as the process differs quite a bit from backing up ordinary files. The process of restoring a backup must also be known, as there’s no point in having a backup if the user cannot reliably restore it.
In this guide, we’ll go over various command line examples to back up and restore MySQL or MariaDB databases on a Linux system. You can then use these commands to make regular backups of your databases, or even add them to a Bash script that can do most of the work for you. Another option is to configure cron to make regularly scheduled backups of your databases.
In this tutorial you will learn:
- How to back up MySQL or MariaDB database (one or multiple)
- How to restore a MySQL or MariaDB database backup
How to change MariaDB user password
Have you or one of your MariaDB users forgotten the password to a MariaDB account? It’s very easy to reset a MariaDB user password on Linux, and we’ll show you the commands and step by step instructions below.
Resetting the MariaDB root password requires a different set of instructions, which we also cover below. Depending on which account you need to change the password for (a normal user or root), follow the appropriate section below.
In this tutorial you will learn:
- How to change MariaDB user password
- How to change MariaDB root password
Changing MariaDB user password
Introduction to database normalization: the first three normal forms
The goal of a relational database normalization is to achieve and improve data integrity and avoid data redundancy so to avoid possible insertion, updation or deletion anomalies. A relational database is normalized by applying a series of rules called normal forms. In this article we will discuss the first three normal forms.
In this tutorial you will learn:
- What is the first normal form
- What is the second normal form
- What is the third normal form
How to read and create csv files using Python
CSV is the acronym of “Comma Separated Values”. A csv file is a just plain text document used to represent and exchange tabular data. Each row in a csv file represents an “entity”, and each column represents an attribute of it. Columns are usually separated by a comma but other characters can be used as field separator instead of it. In this tutorial we will see how to read and create csv files using Python and specifically the csv module, which is part of the
language standard library.
In this tutorial you will learn:
- How to read csv rows as a list of strings
- How to read a csv as a list of dictionaries
- How to create a csv using Python
- How to create a csv starting from a list of dictionaries
How to install RegRipper registry data extraction tool on Linux
RegRipper is an open source forensic software used as a Windows Registry data extraction command line or GUI tool. It is written in Perl and this article will describe RegRipper command line tool installation on the Linux systems such as Debian, Ubuntu, Fedora, Centos or Redhat. For the most part, the installation process of command line tool RegRipper is OS agnostic except the part where we deal with installation pre-requisites.
Pre-requisites
First we need to install all prerequisites. Choose a relevant command below based on the Linux distribution you are running:
DEBIAN/UBUNTU # apt-get install cpanminus make unzip wget FEDORA # dnf install perl-App-cpanminus.noarch make unzip wget perl-Archive-Extract-gz-gzip.noarch which CENTOS/REDHAT # yum install perl-App-cpanminus.noarch make unzip wget perl-Archive-Extract-gz-gzip.noarch which
How to change MySQL user password from command line using mysqladmin on Linux
Apart of the MySQL command line interface a a system administrator is able to change MySQL user’s password using mysqladmin command directly from a shell command line. The following linux command will change/update a current MySQL root password given that current password is blank:
# mysqladmin -u root password 'newpass'
How to promote Mediawiki user with sysop and bureaucrat privileges
The following lines will describe a procedure on how to promote mediawiki user to sysop and bureaucrat role directly using MySQL database.
Access database
First, connect to your database using mysql client. Depending on your environment you can run something like:
$ mysql -u USER -p PASSWORD
Once you get to the MySQL command prompt select appropriate Mediawiki database. In the example below the database name is wiki:
mysql> use wiki Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed
Using Adminer to Manage your Databases
Introduction
If you find yourself interacting with a database system such as MySQL, PostgreSQL, MS SQL, Oracle, or even SQLite, sometimes you find that some of the tasks you perform are more conveniently executed using a GUI rather then using the default management utility (usually run from a CLI) provided by the database system itself. Some of you may already use other tools such as phpMyAdmin, or phpPgAdmin. This article will talk about another web based database management tool known as Adminer. Adminer allows for the management of all the database systems mentioned above.This article covers Debian (& Ubuntu), Fedora, and ArchLinux.
From its website: Adminer (formerly phpMinAdmin) is a full-featured database management tool written in PHP. Conversely to phpMyAdmin, it consist of a single file ready to deploy to the target server. Adminer is available for MySQL, PostgreSQL, SQLite, MS SQL and Oracle.
Adminer has an entire page dedicated to a comparison between itself and phpMyAdmin. Some notable features in Adminer that are either absent or incomplete in phpMyAdmin include: full support for views, full support for triggers, events, functions, routines, and ability to group data and apply functions to data in select data (to name a few). This article will cover its installation, configuration, customization, and some usage example for MySQL and PostgreSQL.
Pre-requisites
- Have some knowledge in web administration and development (HTML, CSS, PHP, and Apache)
- This article assumes you have Apache, PHP, your database system of choice configured.
- I’ll be running Adminer on a local development LAMP stack I run on my netbook
Big Data Manipulation for Fun and Profit Part 3
There have been two previous article in this series, which you may want to read first if you have not read them yet; Big Data Manipulation for Fun and Profit Part 1 and Big Data Manipulation for Fun and Profit Part 2.
In this series, we discuss various ideas and practical approaches for handling big data, or more specifically handling, transforming, mangling, munging, parsing, wrangling, transforming and manipulating the data at the Linux command line.
This third article in the series will continue explore Bash tools which can help us when processing and manipulating text-based (or in some cases binary) big data. As mentioned in the previous articles, data transformation in general is an semi-endless topic as there are hundreds of tools for each particular text format. Remember that at times using Bash tools may not be the best solution, as an off-the-shelf tool may do a better job. That said, this series is specifically for all those (many) other times when no tool is available to get your data in the format of your choice.
Finally, if you want to learn more about why big data manipulation can be both fun and profitable… please read Part 1 first.
In this tutorial you will learn:
- Additional big data wrangling / parsing / handling / manipulation / transformation techniques
- What Bash tools are available to assist you, specifically for text based applications
- Various examples, showing different methods and approaches