Database

Databases

Databases – why do you need them and what kinds are there?

Databases are a fundamental part of our information society today. They organize electronic data and regulate access to it. Databases have a wide range of applications, both commercial and private. Each database system has a database management system based on a specific database model. While the history of the database began with the hierarchical model, today the relational database model is the...

Protect sensitive data with a strong password

Optimal password protection: how to choose a strong password

It only takes a few seconds for a hacker to gain access to your private data without you having any idea. More often than not, a password is the only means of protection when logging into online services; and if it is too obvious, it will not prove too much of a challenge for criminals to crack. There are numerous options to increase password security.

SQL JOIN

SQL JOIN – queries across multiple data tables

A major strength of the relational database model is that information is stored in separate database tables structured according to semantic relationships. This concept, known as normalization, is the basis for data storage that is as redundancy-free as possible, but requires a mechanism with which data from different tables can be merged for queries. The different JOIN types provide users with...

SQL OUTER JOIN

SQL OUTER JOIN

OUTER JOINs are queries that take place across several database tables. There are LEFT OUTER JOINs, RIGHT OUTER JOINs and FULL OUTER JOINs. Each of these JOIN types has a larger result set than the INNER JOIN. But what exactly is the difference between the individual types? Here, we will distinguish OUTER JOINs from INNER JOINs, compare the different subtypes of OUTER JOINs and explain how they...

Relational Databases

The relational database model

With relational database systems, you use tables to store and manage information. This sounds simple but involves quite complex concepts such as normal forms, key relationships, and JOINs. This article will introduce the basics of the relational database model, compare its advantages and disadvantages, and delimit this type of data storage from alternative approaches, like object databases,...

Set up ownCloud with Raspberry Pi

Creating a Raspberry Pi cloud server with owncloud

With ownCloud software, your Raspberry Pi can be used as a private cloud, performing the same kind of tasks as clouds from major providers such as Google, Amazon, and Dropbox. Cost-effectiveness is just one of many the benefits of creating your own personal cloud; another is the privacy and security of your data. This step-by-step Raspberry Pi cloud tutorial explains how to set up ownCloud.

Extranet

What is an extranet, and how can I use it?

Order status, product compatibility, updated delivery terms – manual transmission of data to business partners by mail or phone takes a lot of time. But this can also be done with less effort. The solution: an extranet. But what is an extranet? How do companies use it? This article looks at how to create an extranet, as well as the benefits and some disadvantages of using one.

MongoDB: an introduction and comparison to MySQL

MongoDB — the flexible and scalable NoSQL database

NoSQL databases have long since been serious competitors to classic relational database systems, like MySQL. They replace the strictly-defined storage structures of traditional models through flexible saving procedures. This allows data pools to be easily distributed onto multiple servers in order to guarantee high availability of web applications. But are these new systems really all that they’re...

How does data backup work for databases?

Backing up your database

Backing up your data is a popular option for securing your database. In order to create backup copies, you need additional hardware and to install a suitable backup structure. How do you secure your own network and web server against attacks and proceed to protect your databases?

Setting up server backups with rsync

Server Backups with rsync

A server backup is the best method for securing the data of your online projects, thereby preventing any damaging losses. Server environments are especially in need of cleverly devised backup strategies that take every type of device into account. Here, backup programs become essential. Free applications, like rsync, offer reliable and compelling alternatives to their expensive conventional...