Database

A comparison of data mining tools

Data mining tools for better data analysis

In the digital age, it’s normal for data from small and medium-sized companies to grow to unmanageable amounts. Data mining tools are used to extract desired information from data sets. These extract recurring patterns from the data and make them available to marketers and statisticians. We have compared the most important data mining software and show where their strengths and weaknesses lie.

What is Big Data?

Big Data: definition and examples

When we shop online, book vacations, and search for gift ideas, we hardly give a second thought to the fact that each search entry leaves behind a trail of our identity. Busy web bots are never far behind and sweep up this information. The result of all of this is Big Data: massive volumes of data that are analyzed and used for a variety of reasons. But is there reason to be wary of leaving behind...

Best cloud storage providers

The best cloud storage providers – an overview of the best online storage

Storing files online on a cloud platform has become part of everyday life for many people. Regardless if it’s your own holiday photos, or important documents for work - storing files with online storage providers takes the load off your hard drive, and also ensures that they are available anytime and from anywhere. But what are the best cloud storage providers on the market? And what differences...

UML: activity diagram

Activity diagrams: clearly present chronological activity processes with UML

UML activity diagrams help you to graphically illustrate the chronological sequence of system processes in object-oriented programming. They show which actions take place in which order to execute an activity. With a finished diagram, you can create code frames using XML transfer. Or do you want to map business processes? We show examples of how to create an activity diagram, which symbols belong...

Database normalization

Less redundancy thanks to database normalization

Redundancies occur when various details are combined in a single database table. These redundancies use up storage capacity and prevent efficient data processing. The relational database model offers strategies for splitting datasets among several linked tables, in a process called database normalization. Find out what it’s all about with practical examples.

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,...