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...

INNER JOIN: definition and application

The INNER JOIN is the most important JOIN type in the relational database model. If you want to query database tables in a group, you would usually use INNER JOINs based on equality relationships between primary and foreign keys. We will show you how to use INNER JOINs in practice, delineate the JOIN type from OUTER JOINs, and also deal with the different subtypes of INNER JOINs.

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...

In-memory databases: the storage of big data

In-memory databases enable big data to be analyzed and made available in real time. The quick access speeds are made possible by storing the data on the working memory – hence the name in-memory database. Traditional databases, on the other hand, are based on the method of storing data on the hard disk. How do in-memory databases differ from traditional database systems? And what are the go-to...

All you need to know: what is a hostname?

A computer’s unique name on a network is the hostname, site name or computer name. The hostname is part of the fully qualified domain name, which can be used (for example) to find and access websites on the internet. Here you’ll learn what a hostname looks like, and we’ll show you various ways to determine the hostname using an IP address or how to change it.

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,...

Error 522 – 'Connection timed out': How to fix the error

52- HTTP error messages indicate a problem between the web server that is running a website and the Cloudflare CDN service. The 522 error is very common and is also known as the 'Cloudflare error'. It is displayed in the visitor’s browser whenever the mandatory TCP handshake fails. This guide explains the reason for this error message and what solutions there are for site operators and visitors.

ERR_SSL_PROTOCOL_ERROR: how to fix the Chrome bug

Chrome is the world’s most widely-used internet browser. The application scores points not only when it comes to security and speed, but also with its features such as cross-device synchronization of user data. But errors can occur even when surfing with Google’s wonder weapon. These can lead to the browser crashing or prevent certain pages from being accessed. The error message...

Hyper-converged systems: The compact data center

The traditional data center could be significantly streamlined by migrating to a hyper-converged system. By eliminating the need for highly complex infrastructures and multiple work areas, the company’s IT department could function more efficiently, dynamically, and cost-effectively. This is made possible using preconfigured standard hardware and a complete virtualization of the IT infrastructure....

QUIC: What is behind the experimental Google Protocol?

Quick UDP Internet Connections (QUIC for short), is an experimental network protocol from Google. Further development of the protocol is being driven by IETF, which has set up a dedicated group working towards it. The QUIC protocol is intended to offer a speed-optimized alternative to the current transport standard TCP and builds on the connectionless protocol UDP to achieve this.

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