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What is Oracle database

Oracle database (Oracle DB) is a relational database management system (RDBMS) from the Oracle Corporation. Originally developed in 1977 by Lawrence Ellison and other developers, Oracle DB is one of the most trusted and widely-used relational database engines.

The system is built around a relational database framework in which data objects may be directly accessed by users (or an application front end) through structured query language (SQL). Oracle is a fully scalable relational database architecture and is often used by global enterprises, which manage and process data across wide and local area networks. The Oracle database has its own network component to allow communications across networks.

Oracle DB is also known as Oracle RDBMS and, sometimes, just Oracle.

Oracle Database features

Oracle Database allows you to quickly and safely store and retrieve data. Here are the integration benefits of the Oracle Database:

• Oracle Database is cross-platform. It can run on various hardware across operating systems including Windows Server, Unix, and various distributions of GNU/Linux.
• Oracle Database has its networking stack that allows application from a different platform to communicate with the Oracle Database smoothly. For example, applications running on Windows can connect to the Oracle Database running on Unix.
• ACID-compliant – Oracle is ACID-compliant Database that helps maintain data integrity and reliability.
• Commitment to open technologies – Oracle is one of the first Database that supported GNU/Linux in the late 1990s before GNU/Linux become a commerce product. It has been supporting this open platform since then.

Oracle Database has several structural features that make it popular:

• Logical data structure – Oracle uses the logical data structure to store data so that you can interact with the database without knowing where the data is stored physically.
• Partitioning – is a high-performance feature that allows you to divide a large table into different pieces and store each piece across storage devices.
• Memory caching – the memory caching architecture allows you to scale up a very large database that still can perform at a high speed.
• Data Dictionary is a set of internal tables and views that support administer Oracle Database more effectively.
• Backup and recovery – ensure the integrity of the data in case of system failure. Oracle includes a powerful tool called Recovery Manager (RMAN) – allows DBA to perform cold, hot, and incremental database backups and point-in-time recoveries.
• Clustering – Oracle Real Application Clusters (RAC) – Oracle enables high availability that enables the system is up and running without interruption of services in case one or more server in a cluster fails.

Oracle Database Editions

Oracle provides three main editions of Oracle Databases as follows:

1) Enterprise Edition (EE) is the common and expensive edition of the Oracle Database. It has the following characteristics:

• No maximum number of CPUs
• No limits on memory or database size
• Include premium features that are not available in other editions.

2) Standard Edition (SE) is a limited edition of the Enterprise Edition that has the following characteristics:

• Limited to four or fewer CPUs
• No limit on memory or database size
• Include many features, but no as many as EE

3) Expression Edition (XE) is a free-to-use version of the Oracle Database that available on both Windows and GNU/Linux platforms. These are the features of Oracle Database XE 18c:

• Limited to 2 CPUs
• Can use the maximum of 2GB of RAM, and has 12GB of user data.
• Very limited features

In this tutorial, you have learned about the Oracle Database, its notable features, and editions.

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